Day 122

Although very short lived and sparse, the flowers of this black radish are very pretty.
The acrylic crocheted netting (left) has held up much better than the cotton trial. In fact it appears to be in good enough shape to wash, and be used again.

The radish appears healthy (right), and I have every reason to believe that the system could continue to support a plant almost indefinitely.

While I wouldn’t exactly call it ornamental, it is interesting looking, and taller than I expected. Someday people are going to quit teasing me about my crochet hydroponics; but not today.

Today, Gentle Reader I give you version three: I started with two plastic colanders from a dollar store, lashed them together, made a hole in the top, and filled with perlite. The encasing shell and wick are crocheted as one seamless piece.

Then I suspended the “ufo looking crochet thing” over the pond, with the wick dangling into the water.My current plan is to top water the perlite to keep it moist, then as the roots grow down to the wick, allow that to water the plant, until finally the roots reach the water, and it begins to function as a deep water culture. At which time, the perlite globe will not longer be supplying moisture, but air. Peace, love, and puka shells,

Grubbycup ]]> http://urbangardenmagazine.com/2010/05/crochet-hydroponics-part-5/feed/ 2 http://urbangardenmagazine.com/2010/04/hydroponic-recirculation-basics-part-3/ http://urbangardenmagazine.com/2010/04/hydroponic-recirculation-basics-part-3/#comments Sun, 25 Apr 2010 00:07:04 +0000 Urban Garden Magazine http://urbangardenmagazine.com/?p=4626 What all Hydroponic Growers Need To Know About Nutrient Recirculation

As we’ve learned in part 1 and part 2, in order to grow successfully in a hydroponic system, there are certain basics that always need to be kept in check: otherwise, plant performance inevitably suffers. After covering source water, nutrient and pH, world-renowned hydroponics expert Michael Christan breaks down the final ingredients of a healthy indoor growing environment: oxygen, light, temperature, humidity, air circulation and CO2.

Photos courtesy of AmHydro.

The 5 basics of recirculation and plant performance:

1. Pure source water
2. Balanced nutrient ions/anions (EC)
3. Optimum pH
4. Plentiful oxygen availability
5. Optimum light/temp/humidity/air circulation/CO2

The Importance of Oxygen

It’s obvious that loose, friable soil with organic matter and thriving microbes grows plants much better than tight, clay soil devoid of organic matter. The primary missing ingredient in the latter is air (oxygen) availability.

The air we breathe is composed of gasses: 78% nitrogen (N2), 21% oxygen (02), 0.9% argon (Ar) and 0.03% carbon dioxide (CO2). The one we’re focusing on in this article is oxygen. The action of microbes on organic matter in a loose soil produces air pockets as organic matter is mineralized. These oxygen pockets are crucial to the survival and rapid colonization of healthy microbial populations. When the organic matter in the soil is fully consumed by the microbes and plants have consumed all the minerals, oxygen becomes depleted and, if more organic matter is not reapplied, plant performance slows and pathogenic (anaerobic) microbes can colonize. This condition is best avoided.

In media-based recirculating systems, the O2 is in the media: e.g. rockwool, perlite, grow rocks. Plentiful air space is available even after water is drained from the media. Roots thrive in O2-rich pockets. They are able to produce prolific root systems and plentiful root hairs to increase surface area to better absorb available ions. This is the best reason for using media with porosity. Of course, flood and drain systems suck fresh air into the media when it drains, which is why it’s such a great irrigation system.

In water-based recirculating systems, NFT, DFT and Aeroponics, O2 availability is intrinsic to the design of the system. NFT is a flat-bottomed tube with a shallow nutrient stream moving slowly, keeping root hairs moist and absorbing O2 (see “NFT Gro-Tanks,” UGM009). Aeroponics is misting droplets of water, increasing the surface area many-fold for roots to grow prolific root hairs for ion absorption. It supersaturates the solution with O2. DFT uses air pumps and water temp to keep roots bubbled with 02 and oxygen rich.

The heart of a media-based or water-based recirculating system is the nutrient reservoir. This too requires oxygenation, especially when water temperatures rise. The use of air pumps and air stones on smaller reservoirs and pump-powered eductors (venturis) on larger reservoirs make a big difference in pathogen suppression (nasty fungi and bacteria don’t like O2). This agitation drives ethylene gas from the solution and increases the longevity of the nutrient. Be sure that, if there are reservoir lids, there’s room for air exchange with ambient air in the room or greenhouse. Many commercial growers use fresh outside air in their eductors to keep the nutrient solution optimum.

Dissolved Oxygen (DO) can be measured to determine solubility of oxygen in fresh water. Fresh water at 72°F (22°C) has a DO of 8.7 ppm; at 82°F (28°C) it drops to 8.1 ppm. Salt solutions are lower. As a rule of thumb, every increase of 1ppm in DO is equivalent to an 11°F (12°C) temp drop. The cooler the temp, the higher the DO. You don’t want cold water on plant roots, though. You want 72°F (22°C) water at your roots for most plants.

When we measured DO in our greenhouse reservoirs, we found that a 74°F (23°C) nutrient tank at an EC of 2 had a DO of 6.3 ppm (low because of salts and sitting still). When we turned on an eductor (venturi), which we do in ALL reservoirs, we received a reading of 7.6 ppm. BIG difference. That’s an increase of 1.3 ppm without changing temperature.

Then we add an in-line Mazzei injector in between the tank and the feeder pipe, which raises DO to 8.3 ppm. By the time the water had run down the NFT channel and 18 plants had their way with the O2, with some off-gassing occurring, there was an 8.1 ppm DO left in the nutrient solution going back to the reservoir. That’s what we’re after! Plants thrive at those DO levels. Makes ALL the difference.

Be careful: as water temperatures of salt solutions increase, you must mitigate by adding O2 in the reservoir as well as directly on the roots. If you can’t get the DO level up by mechanical means, then you will most likely require a water chiller, which is expensive but sometimes imperative. If you cannot bring water temps down or increase DO in the nutrient solution, your next action will be disease suppression or inoculating roots with beneficials to out-compete the pathogens that thrive in high temp, low DO water. If you do get a DO meter, get a good one. We use an Extech Model 407510.

Light

Photosynthetically Active Radiation (PAR) light is a fancy term for the wavelengths plants use to vibrate chloroplasts to power the engine of photosynthesis, a vaguely understood process in my opinion. It is said that PAR light is in the 400 to 700 nanometer wavelength range. No big deal if you’re outside or in a well-lit greenhouse. But if you are growing under HID light or using it as a supplement, it certainly is.

Color temperatures of lamps are measured in degrees Kelvin from a color rendering index (CRI). The blue/white side of the spectrum has higher Kelvin temp: 6000K-8000K (MH lamps). The yellow/red side of the spectrum has lower Kelvin temperature: 3000K (HPS lamps). As a rule, the higher the Kelvin temp, the more vegetative the growth. The lower Kelvin temps are used for supplemental and/or flowering light. Different bulbs have different combinations or blends of gasses for better PAR value. Plants can be finicky and prefer one blend of light more than another. Trial and error, sometimes, is the only way to find out what your plants really like.

High Intensity Discharge (HID) lamps produce light when the gases inside the fused alumina tube are heated to the point of evaporation by high voltage electricity. This process forces the metal gasses to throw off a barrage of photons partly in the PAR range. As the bulb burns over time, the metal gasses slowly change form and degrade out of the PAR range. It is not obvious, but plant performance can suffer from lack of the PAR light when there is no shortage of photons to the naked eye. To look at light as a possible limiting factor, keep track of the hours your bulbs have been burning. If you are over the recommended burn range as stated by the manufacturer, that could be what’s compromising your system. Rule of thumb with HPS bulbs is to replace them every 12 months, and MH bulbs every 9 months, with HPS burning 12 hour days, MH burning 18 hour days.

Outside it’s obvious what limits light, like trees. But in greenhouses, if the glazing is dirty, that’s a big deal and that situation just creeps up on you. Depending on what you’re growing and what time of year it is, a dirty film can cut out as much as 30% of available light. If you are using an 85% transmission film and have 30% attributed to dirt, that’s 55%, basically shade cloth. In situations where there is too much light and plants are unable to cope with the leaf temperatures or solar radiation, a white or metallic shade cloth is preferable to black, as black can radiate heat back down on the plant canopy. A simple mistake easily avoided by many growers in double poly greenhouses is that the inflation fan is pulling inside air in between the films, thereby creating moisture that blocks light. You can tell by the droplets in between the films, or a haze. It is always recommended to use outside air for inflation. Of course, all of this is dependent on location, latitude, geography, plant in cultivation and skill/experience of the grower. We cannot cover all those variables in a brief article.

Temperature

Plant response to temperature is pretty obvious. It’s visible. Plants stop growing when root temps hit 58°F (14°C). Air temp can actually be cooler than 58°F, but when roots are cool, growth slows and stops even when air temp increases. When temps are too high, say 95°F (35°C) plus, depending on RH, air flow, light, kind, size, and age of a plant, they may stop feeding and spend their energy evaporating water from their stomata to cool down. Temperature must be managed to keep plants transpiring and active in the sweet spot.

Most temp controllers are effective, turning on fans for increased air exchanges, but when temps are too hot outside, air conditioners must be used. As a variable, though, temperature control is straightforward. It’s common knowledge that insects like very consistent temperatures and no air movement. Find which temperatures are your best high and low, and vary them morning, daytime and night. Keep an inhospitable environment for the pests without sacrificing plant performance: another dance to master.

Humidity

The two ways of explaining humidity are relative humidity (RH) and vapor pressure deficit (VPD). Most people are familiar with RH and use hygrometers so, for the purposes of this article, I will use RH.

In my experience, this is the one variable that most growers need to be more aware of. The dance between temp/humidity directly affects transpiration rates as poor transpiration opens the plant organism to disease and mineral deficiencies.

RH is the amount of water vapor present in the air expressed as a % of the amount needed for saturation at the same temperature. Here’s what that means: if the humidity is too high, e.g. 95% at 75°F, plants cannot transpire or evaporate enough water to pull minerals up the vascular system even with stomata wide open. This usually results in calcium (Ca) deficiency (remember, Ca is a non-mobile element and must be constantly supplied to growing tips) and plant stress, which increases their vulnerability to fungal intrusion.

If humidity is too low, 50% at 75°F, stomata will open in an attempt to evaporate water because of the low pressure around the leaf, but then close up to conserve cell pressure in the leaf. Plants stress as they cannot take in CO2 with closed stomata and growth stops as the plant is just trying to survive without going into wilt (i.e. loss of leaf turgidity from which it’s difficult to recover). Again the plant is vulnerable to disease and insects. These two extremes points will create a high probability of crop loss.

As a rule, at 75°F (24°C), if RH is below 60% you must add moisture to get to 75% (which is ideal), but stay below 85% to avoid stress and disease. At 85°F (29°C), if RH is below 70% you must add moisture to get to 80% (which is ideal), but stay below 90% to avoid stress and disease. As temperature rises, air holds less moisture. Steer your plants within these parameters for optimum plant performance.

When RH is too low, use a fogger or humidifier coupled with outside air exchanges. When outside air is too warm and dry, you will have to use some form of air conditioner (if that is the only way) to drop the temperature to increase the moisture-holding capacity of the air.

When RH is too high, raise temperature to reduce moisture saturation of air coupled with outside air exchanges. If outside air has too high of an RH, you will need a dehumidifier to pull water out of the air.

Transpiration is king. Monitoring transpiration rates and keeping them optimum with temp/RH manipulation is crucial. If you are outside of the temp/RH safe zones and don’t use some mechanical method of bringing them under control, you will always be fighting the results of that variable being unchecked. This is where high quality environmental controllers come in handy

You can buy the most expensive nutrients, goodies and gadgets available to grow your crop, but if your plants are unable to transpire and you don’t know that, you had best learn quickly or get a day job

Air Circulation and CO2

No matter what kind of controlled environment you’re running, greenhouse or greenroom, air circulation is another key component that is often overlooked until mildew takes out your crop or your plants starve from lack of CO2. The great outdoors takes care of all this, but inside you have to provide the controls or fall prey to what you didn’t know you didn’t know.

Rule of thumb: 60 air exchanges per hour. Not only do you need to flutter your plants with gentle breezes from an oscillating fan or horizontal air flow (HAF) fans in a greenhouse, but you must freshen the air with air exchanges from outside, taking advantage of the 385 ppm ambient CO2. The raw materials that PAR light makes into carbohydrates are CO2 and H2O. CO2 furnishes the carbon and oxygen, while water furnishes the hydrogen for the carbohydrate (CH2O).

If air exchanges are frequent, 385 ppm CO2 is plenty unless you’re looking to accelerate growth by enriching your space with higher levels to, say, 1500 ppm CO2. Even if you are adding CO2, you still must exchange air. There are numerous ways to provide CO2: chemical reactions, gas bottles, gas generators and a variety of controllers and monitors depending on the size of the operation. For the purpose of this article, you just need to know that it is a basic component of the indoor growing environment, and be mindful that it’s always available. Without CO2, plants will not grow.

One of my teachers, Grenville Stocker in NZ, took me into one of his client’s lettuce/herb greenhouses and asked me, “Would you get a chair, sit down, read a book or hang out in here all day?” Actually, it was way too moist, not enough air movement, my shirt was sticky, and it was uncomfortably warm. I said, “No way.” He remarked, “How do you think those plants feel? The same way, I reckon, except they can’t leave.” Then he showed me powdery mildew in certain areas, a thrip infestation and tip burn in some of the lettuces. The plants did not look vital, they looked stressed. I noticed the HAF fans were down, because of a blown breaker that the grower had been meaning to fix for a week. He had an RH monitor but no controller to check humidity and spill air or add heat … AND he was doing only 1 air exchange per hour because it was cold outside. He wanted to keep temps up inside without turning on the heat, which would cost him money. I looked at the RH: it was 95%. Temp was 80°F but it felt like 90°F because of the humidity. His client was too busy to pay attention or take coaching, and he wasn’t even there. Grenville always tested me; he’d say, “What’s wrong with this picture?” Then he would point out a basic that was obvious once I saw it. Most problems were easy to correct once distinguished.

I found out later the grower lost 50% of his crop and the other 50% was barely marketable. Had he kept HAF fans working, increased his air exchanges and turned up the heat to drive off the humidity with the help of a controller, he would not have had crop and financial loss. Just that one error cost him a market: he couldn’t deliver, so a competitor moved in. The point I’m making is: don’t leave your plants in an environment you can’t handle being in yourself. Use meters and controllers, but always keep them honest by paying attention to what your skin says.

All the variables of light, temperature, humidity, air circulation and CO2 must dance together in a harmony that you must monitor and control to be successful and avoid crop loss. If you cannot distinguish which variable is out, you will be guessing what the problem is and perhaps taking actions that are detrimental. Next time a problem arises (which inevitably will happen) and you’re scratching your head as to what to do, go through this list and check off each one that you KNOW is in tolerance. These 5 basics could be what you didn’t know you didn’t know. Now that you do, dissect them and become competent with each one:

The 5 basics of recirculation and plant performance:

1. Pure source water
2. Balanced nutrient ions/anions (EC)
3. Optimum pH
4. Plentiful oxygen availability
5. Optimum light/temp/humidity/air circulation/CO2

For the content and experiences that allowed me to write these articles, I’d like to thank my teachers, Grenville Stocker (Stocker Hort), Jeff Broad (AutoGrow), Genaro Calabrese (ex partner), Grant Creevey (Accent Hydro) and all our clients and associates for sharing and being open to “figuring it out.” Controlled environment plant cultivation is infinitely beguiling; I am always learning a greater respect for being part of that process. Genaro’s motto: “Every plant, every day.”

Good luck and good growing.

Michael Christian, the president of American Hydroponics since 1984, is a hydroponic system designer and consultant to commercial growers worldwide.

It’s both. Water from the koi pond is filtered through a series of 4 wooden half-barrels.

In this way, I get both a cleaner pond, and attractive, almost maintenance-free plants.
Each barrel is slightly lower than the one before.

Pond water is pumped into to the top half barrel, and gravity takes care of the rest. These plants are obviously not nutrient starved. From the levels they get in these last two, I’d say the system could support another pot or two.

If I were to use a more traditional design, I would have pots that needed added fertilizer to do well, and a normal pond filter to remove unwanted elements from the koi pond.

By combining the two, not only do I avoid expenses like fertilizer and new filters, I avoid the work in adding and changing.

I do not claim this system to be maintenance free, but most of the time all it needs is simply clearing the pump intake, or removing plants so they don’t overgrow.

Peace, love and puka shells,

Grubbycup ]]> http://urbangardenmagazine.com/2010/04/half-cooked-thoughts-pond-filter-or-hydroponic-planter/feed/ 4 http://urbangardenmagazine.com/2010/04/what-is-permaculture/ http://urbangardenmagazine.com/2010/04/what-is-permaculture/#comments Thu, 08 Apr 2010 21:36:29 +0000 Urban Garden Magazine http://urbangardenmagazine.com/?p=4364 Javan Kerby Bernakevitch, a permaculture designer and teacher-in-training, introduces us to the principles and practice of permanent (agri)culture.

“Permaculture is revolution disguised as organic gardening.”
- Graham Bell, from Permaculture – A Beginner’s Guide

Permaculture is not organic gardening, and I am not a gardener. What I am is a permaculture practitioner who uses organic gardening, and many other tools, to design systems that work to water, feed, warm, house, and provide community, not to mention: make a garden.

So if permaculture isn’t just gardening, then what is it?

Permaculture is not the rain that falls, nor the roof that collects it or the catchment systems that stores it. Permaculture design is the relationship between these things. Permaculture is the match maker, creating passionate love affairs between rain and plants, humans and animals, and ultimately achieving systems that produce enough natural resources to provide for their own maintenance and reproduction.

Rainwater collection.

Imagine a ball that drops, hitting a lever that turns a wheel pulling on a string attached to a light bulb. Each step creates the necessary conditions for consequent steps which eventually will turn on the light bulb. Similar to well set-up dominoes. We can learn the skills to design whole systems that are focused on goals and fixing problems at the source, instead of focusing on the symptoms.

A backyard graywater filtration system that takes the sink, shower and washing machine water from the house, passes the water through a strainer, and then filters it through this man-made wetland bedded in 4 bathtubs that irrigates the gardens directly. Those irrigated beds produce 10-20% more than the non-graywatered beds.

Graywater filter.

With the light bulb glowing over your head you might have realized that practicing permaculture is not all that difficult. In fact, you probably are practicing it already and don’t realize it. Why? Because the knowledge contained under the umbrella of permaculture is not new; it combines the ancient and traditional knowledge of growing food with the modern science of ecology and new technology. Work in permaculture is self-evaluating: either it works or it doesn’t. The beauty of this movement is that, if you can learn from your errors, you can learn to design systems that work. You don’t have to wait for a committee to stamp your certificate or a teacher to baptize your understanding through tests.

“If you’re a scientist, you could liken it to a miraculous wardrobe in which you can hang garments of any science or any art and find they’re always harmonious with, and in relation to, that which is already hanging there.”
- Bill Mollison, the godfather of permaculture

Permaculture is a way of looking at the systems that sustain us, and designing them to have built-in endurance and sustainability to gain the highest output from the lowest input. It is not just the organic garden: the garden is just a piece of the bigger picture. A picture that includes the local climate, site topography, water access and drainage, capacity of the land and its users, where income is produced to finance the whole process and a host of other items. It is looking at the pieces of life and designing systems that produce the basic necessities needed to sustain and provide joy while creating rich, wealthy lives.

“Wealth is a deep understanding of the natural world.”
– Inuit definition

“I think it’s pointless asking questions like ‘Will humanity survive?’ It’s purely up to people – if they want to, they can, if they don’t want to, they won’t.”
- Bill Mollison

Bill Mollison, a disgruntled and highly motivated biologist, culminated a true “aha” moment with student David Holmgren in 1978 when they set out the seminal work Permaculture One. Coined as a combination of the words permanent and agriculture, and then permanent and culture, permaculture from its textual origins is about creating a world were we can live indefinitely. In this work, Mollison and Holmgren articulated their thoughts on sustainable living through a positive action movement in which anyone could be involved. The publication helped to create the first texts for the personal educational keystone of the movement: the Permaculture Design Certificate (PDC). Any keeners out there will be able to find PDC courses being offered in online and hands-on formats.

“If people want some guidance, I say, just look at what people really do. Don’t listen to them that much. And choose your friends from people who you like what they do – even though you mightn’t like what they say.”
- Bill Mollison

Contrary to the parental adage “do what I say, not what I do,” Mollison urges those interested to watch and see what is really happening. In a way, that’s how permaculture started. Working in wildlife relocation, Mollison realized that a forest needs no watering, weeding, fertilizing or other “outside care.” The forest is self-perpetuating. Mimicking the ecological principles he observed in the forest, he conceptualized that he could “make a system” that could produce food for human consumption. In essence, a food forest. This self-described “revelation” was understanding that there are beneficial interactions between living and non-living components. As people, we can assemble those components together to create beneficial connections and yields.

When Mollison asked an elderly Greek woman in a vineyard why she planted roses among her grapes, she replied: “Because the rose is the doctor of the grapes. If you don’t plant roses, the grapes get ill.” Accustomed to science, this answer did not sit well with Mollison. He began to research and found that the rose produces a certain root chemical that the grape root uptakes, which in turn repels the white fly (a pest for grapes). The story is the same from both Mollison and the woman’s perspectives: the grapes grow in community with the roses. However, the understanding behind the story changed. This story is where permaculture can be understood: in nature, organisms work in relation with one another. And using our commonsense we can observe these interactions, work out the commonsense or scientific understanding of what is happening, and reassemble the principle behind the interaction to create systems that feed, clothe, house, warm, and provide us with community.

Now in its fourth decade, the permaculture movement has spread like wildfire, creating a global grassroots community. Global in scope and adoption, permaculture has been able to specialize to meet specific needs. As permaculture is not an ideology, but rather an idea, it can change and adapt to any situation. In Haiti, permaculture practitioners were on the ground shortly after the earthquake, providing safe drinking water and human sanitation with a fraction of the budget of other aid organizations with twice the results. These efforts have grown from solid ethical building blocks that help guide the intentions of practitioners. These ethics, in order of priority and importance, are: Earth Care, People Care and Fair Share.

Earth Care

“We are sufficient to do everything possible to heal this Earth. We don’t have to suppose we need oil, or governments, or anything. We can do it.”
- Bill Mollison

“The Earth is a living, breathing entity. Without ongoing care and nurturing there will be consequences too big to ignore.”
- David Holmgren

Humanity has withdrawn so much of the natural capital from the earth’s savings account that we are no longer living off the surplus interest; we are now eating into the capital itself. We’re living on the savings, and they’re running low: it’s a lot like college without the getting-more-educated bit. From the north to south pole, to the tip of Mt. Everest and the bottom of the ocean, our environment is degraded and degrading at an alarming rate (imagine 1,000,000 fire alarms going off in a closed phone booth and you’re close to how serious the situation is). Synthesized chemicals at toxic levels can be found in every environment, in newborn children, and even in pollen (121 herbicides, fungicides and insecticides at last count); these are the very building blocks that support life.

Think of it this way: if you were hospitalized and depending on a medical life-support system, would you jiggle the plug, poke holes in the feeding tubes or pour toxic waste in the IV bag? Not unless you’re Keith Richards or a cockroach, and even then I think they’d both think twice about it … at least the cockroach would.

Earth Care is the top priority. Earth Care is our top priority. As a curmudgeonly 63 year old farmer from Manitoba advised, after I asked what I should grow on a certain piece of land…

Me: “What should we grow here-”

Him (cutting me off): “Soil.”

Me (frustrated but respecting my elder): “Right, I understand that, but in this micro-climate, what would be good to propagate-”

Him (cutting me off again): “Soil.”

Me (realizing there might be something he’s trying to tell me): “Okay, so you’re saying I should grow…”

Him (finitely stating): “Soil.”

At present, our greatest threat to humanity is not climate change (though that affects soil loss), nor pollution (this does affect soil loss), nor deforestation (now, that really affects soil loss). Our greatest threat is … soil loss. Without healthy ecosystems, soil is destroyed. Without soil, there is no food and, without food, the chairs around our global table become vacant. And it gets rather lonely sitting by oneself.

People Care

“I cannot save the world alone. It will take at least three of us.”
- Bill Mollison

Me, myself and I. Okay, and you too. And you can join, and … well heck, let’s invite everyone to the party. After ensuring that our life-support system is tended to, we turn to each other realizing that if the entire human species is on a planet with finite resources then we in turn all affect and effect each other. Like it or not, we are all in this together. In a closed system, the actions of one are felt by many, detrimental or beneficial alike. In permaculture, and life, everyone has something of value to bring to the party.

In a scarce economy, resilient employees embody the same strategy that ecology demonstrates: an organism that places itself in the most service to the whole, survives. We can see how helping friends and family survive supports our personal survival, and we may evolve a matured ethic that sees all humankind as friends and family and thus life itself as our ally. People care then turns into species care and we too have the “aha” moment that Sister Sledge had: “We are family.”

Fair Share

Remember kindergarten? No, not the dirt eating (which thankfully we don’t have to resort to … yet), but the idea of sharing. Well, sharing is back in style, sharing is the new khaki. With a new twist, fair share is also about abundance. Surplus is created either through an extraordinary amount of effort, which turns into a deficit of time and energy, or by limiting consumption. By conserving resources and setting limits to consumption, we can set our best course for survival to include others while creating the conditions to further the two ethics above.

The Prime Directive of Permaculture

“The only ethical decision is to take responsibility for our own existence and that of our children.”
- from The Permaculture Handbook, by Bill Mollison

Under the prime directive of permaculture, the three ethics (Earth Care, People Care and Fair Share) guide us to devise methods of applying them to our gardens, land, economies and nature. We can see permaculture as “the mechanism of mature ethical behavior, or how to act to sustain the earth” and our existence on it.

Well, if this hasn’t blown your mind yet then strap in for round two … how to go about applying and practicing intentional permaculture. From the prime directive and the ethics we spiral outwards to principles, strategies and, finally, techniques. These three are the holy trinity of permaculture in action.

Principles

Principles are beneficial as there are no penalties for error, only learning from errors, thereby leading to new ideas and methods. Now, here’s where the idea of permaculture being open-source really gets going: at a recent permaculture teachers’ training session, the facilitator (a long-time permaculture practitioner and teacher) stated that she knew of over 372 principles related to the movement. 372? Yup, 372. And by the time you start practicing permaculture, I’m sure you’ll have come up with a few more, or remember one that your grandma used to use. My Ukrainian Baba used to bellow from the top of the stairs when my brother and I were rough-housing: “Smarten up or I’ll throw you out, one by each!” The humor (or maybe it’s the genius) of this maxim lies in the translation to English: those parts that do not work with the overriding ecological principles at play (like my Baba’s patience, or the ability of the earth to absorb the pollution we are producing) are “thrown out, one by each.”

As you move further down this rabbit hole you’ll find many principles. However, I found permaculture best sampled like a good buffet, in sizable portions. David Holmgren, the other author to the first book of permaculture, continued down his own path and has produced some excellent work, including 12 concise principles that are easy to remember and to implement. Some of my personal favorites of his are:

Integrate Rather Than Segregate

The three sisters. Photo credit: Abri Beluga.

This principle has always wowed me by providing concrete examples of how to integrate plants together in communities or guilds that provide for the needs of other plants. The traditional example in North America is the “three sisters,” or maize (corn), beans and squash. Benefiting from each other, the maize provides the structure for the beans to climb (no poles needed). The beans fix nitrogen for the soil and the other plants, while the squash vines spread along the ground, blocking the sunlight that weeds need. The squash leaves are also a “living mulch,” creating a microclimate that retains moisture while the prickly hairs on the vines help deter pests. This guild integrates while utilizing the “waste” of the other plants, thereby touching on another great Holmgren principle: Produce No Waste (meaning that everything can have a use, even if we call it “waste”).

The Mollisonian Permaculture Principles that stand out for me are:

Work With Nature, Rather Than Against It

The revolutionary Masanobu Fukuoka (you’ll thank yourself if you read his The One Straw Revolution) once remarked, “If we throw nature out the window, she comes back in the door with a pitchfork.” When insecticides are used, the predatory insects (insectivores or cannibals, as I like to call them) are wiped out with the pests, ensuring that if an explosion of pests proliferate next year there will be no predators to keep their populations in check. Consequently, more insecticides are sprayed, tipping the scale even more. All pests are never killed and the survivors’ resistance is bred into a new generation, riding nature’s pitchfork aimed right at our food crops.

Visible through this window in the south side of a cob building is a frost peach growing on Vancouver Island. Peaches are not typically grown on Vancouver Island, but this tree is thriving because of the heat absorbed by the structure and the resulting microclimate.

The Problem is the Solution

Everything works both ways. It is only our perspective that judges a thing to be beneficial or not. If the south side of the greenhouse is constantly facing the sun, construct that side out of glass or plastic (salvaged, if possible) and, as the north side never receives sun, let’s construct that side out of a substance that has thermal mass (think of it like a thermal battery: it can up-take heat and return the heat to the surrounding area) like rock, cob (a traditional building material made up of clay, sand and straw), or something else that absorbs solar heat.

A greenhouse with south-facing glass and a north cob wall to retain heat.

Moving swiftly along strategies, like the ones below, are just like a handy number two Robertson screw driver or your Felco pruners: a tool to aid you on your permaculture journey.

When designing any site, be it a garden, a house, or even a driveway, here are the first three things to consider, in order:
1. Water
2. Access
3. Structure

1) Water – No matter where you travel or what you do, water is where the chemistry of life occurs. It’s also where some of your biggest headaches or joys can come from. First, consider where your water source is. Is it close to land that has a lot of sun in all seasons? What’s the land like around the water source? Where does it recharge from (underground, a stream that comes in from your neighbors’ property, precipitation)? Next, where does the water go? Does it drain on the land? Is that drainage seasonal or consistent year-round? If water is life, understanding the nature of your water on-site can save thousands of hours and just as many aspirin or cups of willow tea.

2) Access – As people, we design systems to water, feed, warm, house and provide us with community. If we design those systems first and then go to design access, we may find that the 6′-wide bed is too big for us to garden from the side. Considering how much a system will have to be “bumped” up against informs our decisions on how and where to construct that system. For example, chickens (the official permaculture mascot) need daily feeding (input) and collection of eggs (output). As keepers of this system, additional time and strain is endured if the chicken coop is placed far away from the house. Thus, if a system is “bumped” up against constantly, then placing that system closer to where we are increases the yields (outputs) while decreasing the work (inputs). This also applies to pathways, driveways, and other forms of getting to and away from systems.

3) Structures – Now that you know the water is draining on the north side of the hill and the best vehicle access is from the south, siting your structure can be made by an informed decision. In North America 40% of all energy consumed is by building and maintaining structures. With such huge amounts of resources inputted into your structure (house, greenhouse, tool shed), it’s important to site your structure where water is accessible and not threatening, and access is easy and not labor intensive.

“Permaculture is the end of the lawn virus, symptomatic of consumer culture.”
“You could say it’s a rational man’s approach to not sh*tting in his bed.”
- Bill Mollison

Or perhaps the definition is: “it’s sustainability, distilled, served straight up.” Or maybe it is just understanding that silver bullet solutions are best left to werewolves, proving that silver bullets are as fictitious as their intended fantasy targets. Catch-all solutions like pesticides and magic pills always have unintended side effects: it’s best to address the problem at its source.

As Geoff Lawton (the architect behind the Youtube video “Greening the Desert” — worth the time to watch) says, “All life’s problems can be solved in the garden.” Maybe permaculture is all about organic gardening … however, you’d do well to discard the definitions and just go out there and continue to garden, add in a sprinkle of permaculture, and be fruitful and mulch apply.

Javan Kerby Bernakevitch is an environmental educator, professional communicator, facilitator and editor. An O.U.R. Ecovillage resident on the West Coast of British Columbia, Canada, Javan continues to expand his knowledge and passion for sustainability through permaculture as a designer and teacher-in-training.

Join the discussion on how to incorporate permaculture principles into the indoor garden: post your comments and questions below!

Over in Europe, NFT has been the preferred hydroponic method among hobby growers for many years. Now finally, it seems, the word is beginning to spread to hobby growers over on this side of the Atlantic. But what’s the real deal with NFT? Does it truly offer all these promised benefits to hobby growers without any catches or compromises? Is it just suitable for salad crops or can it deliver when applied to heavy, fruit-laden annuals like tomatoes and cucumbers?

Our main man with a high yielding plan, Everest Fernandez, takes a first look at NFT Gro-Tanks and shares some of his hands-on experience.

WORDS: Everest Fernandez

NFT 101

Ok, don’t be shy. Raise your hand if you don’t know what the hell NFT is. No worries! We’ve all been there, and that’s what I’m here for I guess …

NFT stands for Nutrient Film Technique. It refers to a general method of growing plants hydroponically. In NFT nutrients are added to water just like any other hydroponics system and this solution is contained in a tank. Plants sit on a grow tray above the tank and the nutrient solution is pumped up to the tray. The tray is positioned so that it lies on a slight gradient. The nutrient solution flows constantly over the roots feeding them all the nutrients and water they need. Any nutrient solution that is not up taken simply flows back through a hole into the tank where it is re-circulated.

But What Are The Plants Growing In?

The roots of your plants are constantly bathed in an oxygen-rich nutrient solution. It forms a thin ‘film’ about 0.03 to 0.1 inches in depth. A thin layer of capillary matting called “spreader mat” is first placed over the tray. This helps to spread the flow of the nutrient solution evenly over the entire surface of the grow tray. We all know that roots hate light. That’s why they tend to stay under the ground in nature! Fortunately the root zone is protected with a piece of Correx (kind of like a cross between cardboard and plastic). Small holes are cut into the Correx, just big enough for the base of the plants to fit through. This also helps to prevent algae growth in the root zone or nutrient solution.

Cucumbers grown in an NFT system.

The thin nutrient film not only provides your plants with all the water and nutrients they need, it also gives them access to loads of oxygen – essential to maintain key metabolic processes in the root zone that regulate how efficiently your plants can feed. This is a key feature of NFT. There are always some parts of the root zone that have more access to oxygen than others – simply because they are higher up: these parts of the root zone help to supply lower parts with all the oxygen they require. This is just one aspect of plant physiology that NFT growers exploit to their advantage. When plants have access to all this water, nutrient and oxygen simultaneously the growth rates can verge on being scary.

Gro-Tanks vs. Gullies

NFT Gro-Tanks can accommodate a far wider root system than the NFT ‘gullies’ you may have seen on commercial hydroponic farms (commonly used to grow basil and other leafy greens) making them ideal for plants that produce abundant root systems such as tomatoes.

Go With The Flow

NFT Gro-Tanks often come supplied as a complete kit for hobbyists – including the right sized pump. Solution flow is generally unimportant but should normally be between 1 to 3 pints (400 ml and 1500ml) per min. Channels should be sufficiently sloped, normally not less than 1:50 but may be much steeper if set-up allows, so that there is no “pooling” in the channels.

Plant Stability

What about heavy, fruit-bearing plants like tomatoes? Surely without any growth media, the plants are simply going to keel over due to their own weight, right? Amazingly, the plants form such a thick mat of roots underneath the Correx that they are very well supported. That’s not to say that some top heavy varieties won’t benefit from some net supports – but that’s often the case across the board when you grow plants near to their maximum capacity!

Propagation

NFT growers start their seedlings and cuttings off in the regular way, perhaps propagating in rockwool cubes or another inert media (e.g. net pot with clay balls.) Aeroponic cloning machines can also be used. Just as with any other hydroponics system, it’s really important to ensure that your seedlings or cuttings have a sufficiently developed root zone before transplanting them into an NFT grow tank. Don’t just wait for one or two roots to poke out. Aim for a mass of roots first! A great tip is to use an air-pruning tray (see UGM005, page 28) to generate a compact, dense root zone that’s bursting to break free!

Everest’s NFT Grow-Tank Tips

Here are some of my special tips learned the hard way:

1) If you are using rockwool starter cubes, ensure that the ridges at the bottom of the cube are in line with the nutrient flow, not perpendicular to it. Otherwise your nutrient flow will be impeded.

2) No growth media around the root zone means less insulation and less protection from extremes in temperature – so you need to have your garden’s environment dialed in. The temperature of your nutrient solution is also crucial – but this is no different than with other hydroponic applications. Try to keep your nutrient solution at around 65°F for high levels of dissolved oxygen and optimum nutrient uptake.

3) Plants grown indoors under lights will take up water at a greater rate than they take up nutrient. Over time the EC (CF) of the solution will rise. Regularly top up your tanks with water or 50% strength nutrient solution. Keep your top up nutrient solution in a separate barrel rather than using water straight from the tap.

4) Maintain the pH of your nutrient solution at around 5.8 – check regularly as it can rise as the plants feed.

5) As a general rule, drain your nutrient solution and replace with a fresh batch every 7 to 10 days for optimum yields. Obviously bigger tanks can get away with less frequent changes whereas bigger plants prefer more regular fresh nutrients. For more information on nutrient change-outs make sure you read ‘Maximizing The Nutrient Environment’ by Lawrence Brooke (UGM004,005,and 006).

6) Do not let any light leak into the root zone. Ensure the holes in the Correx cover are just big enough for your plants to fit through. Cover the bases of your plants to prevent green algae forming – especially important if using rockwool cubes.

7) Thoroughly clean your tanks in between crops with a soap solution and rinse thoroughly.

Wait until roots are showing out of your starter blocks before inserting them into your NFT system. This is absolutely crucial!

9) Use a half strength nutrient solution to start your plants off, moving to two thirds to full dosage rate (as detailed on the bottle) after the first nutrient solution change (about 7 – 10 days after planting).

10) Take the opportunity to observe your plants’ root growth directly by simply lifting up the Correx cover!

11) Make sure you completely remove plastic wrapping from rockwool cubes or remove pots if using soil or coco. This allows the roots to access more oxygen.

12) NFT is a bare rooted growing technique. All but the smallest of plants will need additional support, i.e. yoyo’s or pea netting.

13) Cut lengths of spreader mat long enough to allow an overhang of a few inches from the channel into the tank. No trickling water sounds!

14) Don’t crowd them! Plants grow incredibly fast in NFT Gro-Tanks – many growers are overwhelmed!

Think NFT – Think Sushi!

NFT constantly provides plants with the opportunity to feed rather than other methods which just provide several opportunities to feed. It’s a bit like sitting in one of those once-trendy sushi conveyor belt restaurants all day, every day. You, like your NFT plants, can take what they want, when they want it, rather than having to wait for their next feed. As a result, you and your plants are going to end up very happy and heavy!

Planting out and Irrigation

First, mark your planting sites with a marker on the Correx sheet. Do not position any plant too close to the pump. Make the holes just big enough. The aim of the game is to allow your cuttings or seedling access to the nutrient film without letting light in through gaps. Lay a single layer of spreader mat over the grow tray. Run your pump 24/7, day and night. There’s no need to work out irrigation cycles and frequencies. Your plants will simply absorb as much or as little nutrient as they require. This is perhaps one of the most appealing aspects of NFT. You should be able to see obvious root activity within 24 hours of planting out. Root axes grow into the nutrient film. Fine root hairs will also grow around the propagation media.

Incredible Root Development

One of the best aspects of NFT growing is the ability to peer at the huge mat of roots that quickly develops underneath the Correx cover. It’s easy to assess the health of your plants – just look for a thick mat of white roots! Watch that the roots don’t get carried away and grow into the pump. (Unlikely, but it does happen.) Clean-up in between harvests is a lot less hassle than with media-based growing methods too, mainly because there is so little media to deal with. This makes NFT Gro-Tanks a great choice for the hobby grower who doesn’t want to endure the regular hassle, expense (and back ache!) of carrying endless bags of soil, coco or clay pebbles.

The Verdict?

Once I tried NFT I immediately saw the benefits, despite grossly overcrowding my Gro-Tanks with waaaay too many plants on my first few attempts. You live and learn. Since then I have come to appreciate that less is, indeed, more!

A greenhouse full of plants grown NFT-style.

Daniel Wilson invites us to rethink what gardening in earth vs. gardening in water really means to the sustainability of indoor gardening.

Allow me to paint you a picture…

It’s a beautiful day in Anywhere, USA. It’s 10:30 a.m. and somebody just woke up, had their herbal tea and is now ready to tackle a long day of transplanting young plants into 7 gallon containers of Sri Lankan coco. They hop into their biodiesel powered 4×4 and head straight for the local grow store to pick up the pallet of coco it’s gonna take to fill those 120 containers. After dropping a cool $1,500 for the medium and another $250 for containers, they load up their rig and jump back on the 101 and it’s off to work. Sound like anybody you know?

There’s obviously a fair amount of energy someone’s just expended and they haven’t even started “work” yet. It’s pretty obvious this is a labor intensive method, but it’s well worth it because they’re growing organically, right? Oh … they’re using synthetic coco fertilizers, run drain-to-waste? But don’t they live in the woods? What happens to the run-off? Thank goodness nutrients come in 5 gallon containers because we’re going to be getting through a whole lotta nutes using the drain-to-waste method, right? Okay okay … I’ll quit this righteous talk. But let’s take a minute to ask ourselves a far more relevant question:

Q: Is it really sustainable to continue shipping millions of pounds of growth media all over the planet?

The current practice of bagging soils and shipping it indiscriminately around the globe has helped propel container soil/coco growing to its current popularity in the indoor grow scene. Though this is, without a doubt, a productive technique, it certainly makes the business of growing in earth a very petroleumintensive practice. Most of the organic growers I talk to take great pride in the natural grow medium they use and feel it’s the ecologically appropriate way to garden … as nature intended. Very few growers consider the great costs incurred by transporting that bag of earth conveniently to their local garden shop. The trucking of this relatively abundant resource (earth) has become quite commonplace in both greenhouse and year-round gardening circles. We rarely give a second thought to the amount of energy the bag of earth we depend upon so much represents. In fact, many growers are so confident in the sanity of these perpetual shipping practices that they will buy brand new bags of earth for their next cycle of plants to follow this round. Alas, very few would consider the idea of composting their used grow medium to be used to generate future harvests.

That being said, we need to consider what would happen if the shipping of soils for thousands of miles just becomes impossible … due to regulations on shipping or even a reluctance of a region to want to give up its precious carbon source, perhaps seeing it a better idea to keep it local and grow food in it as opposed to trading it for money. I know, I know, some of this might seem pretty far out and unlikely but it’s these awkward questions that lead us into discussions which begin to propagate solutions for the future. The critical thinking necessary to tackle issues before they become an “issue” is what we need to strive for as a garden and farm-based civilization. Past populations both benefitted and suffered from the methods they preached and practiced. It’s only in hindsight that clarity begins to develop and we are able to steer a course for the better.

So this leads me to our next Q & A.

Q: What is the most sustainable grow medium for the future of indoor and greenhouse cultivation?

For this question there is no simple answer.

1) The renewability of coir fiber is promising, but unless coir is a local product we are still faced with the shipping issues.

2) Naturally derived soils are another obvious option but, as with coir, unless we can solve the shipping dilemma it too falls short with regard to its practicality over time.

3) Stone wool (aka rock wool) products are a mainstay of commercial growers and are a fairly sustainable option – but it takes intense amounts of energy and large factories to process into forms well-suited for plant cultivation. And there’s still the matter of shipping, as far as from Holland to California at times: yikes.

4) Regional soils offer a pretty attractive option as we could build soils from an area’s most naturally occurring resources. This might mean West Coast Soils, East Coast Soils, Deep South Soils … you get the gist. This would make for minimal shipping, and it just makes sense.

5) Expanded clay pellets are another option with a light and dark side. Though made out of naturally occurring inputs, it (like stone wool) is energy intensive to make and costly to ship. More often than not it’s coming all the way from Germany!

6) Local water sources all over the planet offer a reusable and renewable way of growing healthy food, fiber and medicine. It’s possible to pump water vertically from indigenous terrestrial aquifers, or when available, benefit from naturally occurring snow melt driven by gravity.

Is it really possible that water could be considered a viable alternative to growing crops in a conventional substrate? What about plant nutrition? This leads us to our next question …

Q: Besides Aquaponics, don’t most high performance water culture applications rely on inorganic nutrients to work most productively?

Hydroponic applications use mineral salts to provide plants with the nutrition they require to grow and bloom. Most hyper-oxygenated water culture methods tend to greatly increase the efficiency of nutrient uptake in the plants’ root zone. This, in turn, maximizes these naturally occurring earth elements by offering them to plants in their most available forms. Typically you can run your nutrient solution at 40%-70% strength when compared to regular application recommendations for any given nutrient. Combine this with the closed loop nature of the majority of water culture applications and you are feeding your crops and also managing our planet’s most precious resource in a responsible, efficient manner.

Q: Isn’t that still using petroleum-intensive inputs to grow plants? So what’s the difference between this and using petroleum to ship soils?

Most notably, the difference is the reduced emissions from the avoidance of burning fossil fuels to ship transcontinental distances. Besides, this efficient nutrient uptake and constant recirculation gets the most out of both the nutrient and the water. Dissolved minerals in solution make the need for a conventional growth substrate relatively unnecessary in modern gardening applications. This can result in another way for gardeners to save.

Now let’s really get down to the bottom-line with this whole water angle:

Q: Sure seems like it takes a lot of plastic to make a hydroponics system … don’t they make that out of petroleum too?

This is without a doubt the least sustainable aspect to any plastic-intensive hydroponics application. Keep in mind, though, that the majority of soil cultivation is in plastic soil pots … which are often not reused. Most hydroponics systems incorporate as much recyclable content as possible in the form of HDPE (which currently has a LEED rating), PP (Poly Propylene) and other relatively benign plastics. At the present time there are no viable substitutes for PVC & ABS plastics. Hopefully in the not-so-distant future, plant-based polymers may offer a more sustainable substitute. When a hydroponics system is designed and built professionally it should be something that can be used for many, many years. It’s only over this period of time that the practicality of using the plastic finally balances out the negative impact of the plastic itself. With that said, avoid hydroponic plastics if you’ve no intention of reusing it over and over.

Some Conclusions

Whether you’re a fan of soil or water as your grow medium, one thing is for certain: producing consistently good results has to be the common denominator in any crop production strategy. There’s no shortage of different time tested techniques to get sound results. The ever-evolving challenge is how we can achieve the results we expect without disproportionately depleting our planet’s natural resources.

LEDs replacing HID grow lights within the next decade is pretty unlikely, but we can make responsible substitutions as these new technologies become available. Modern water culture methods are one of the most implementable techniques we can use to reduce our carbon footprint as growers. Though not perfect, water culture provides a genuinely organic grow medium at the turn of a wrist. Put down that bag and pick up the hose.

Some final food for thought:

Plant life as we know it conceivably evolved in the oceans long before our earth’s mantle was broken down into what we now consider soil. It was only when single-celled organisms came to the rocky shores of these primordial continents that terrestrial plants even began to exist.With that said, all plant life has its most ancient DNA, which is still able and very willing to adapt back to water. So if the seas were the Petri dish that plant life developed in, isn’t the ocean essentially just a constantly circulating, well-aerated solution of H2O and dissolved salts? Sound familiar?

Below are some pictures of the way to PROPERLY install the ChillKing/IceBox combo—unlike what I had done previously.  Take note of the new hoses and worm-gear clamps used to secure everything.  Your local hardware store will stock a variety of typically cheap hoses.  The hoses from Hydro Innovations are industrial quality and tailored to their cooling and CO2 generator systems—-perfect diameter, inner and outer.  The most significant differences between HI’s hoses and the average water hoses are HI’s superior insulation and kink-resistance.  The vinyl black hoses kink and have no insulation.  Bad for chilling.

Removing my old hoses, I prepped the complete re-hosing by drilling through my garage wall.  With a quality hose setup, I removed all of the hack-job connectors which I previously utilized (see Chillaxing with Hydro Innovations, part 1).  The entire system is powered by an 1850 GPH submersible water pump sitting in my water reservoir.

After teflon-taping all hose bibs, because I am paranoid about leaks, I connected all of the hoses and cinched them with worm clamps.  From the ChillKing, we feed the cold hose into the first of two IceBoxes, then to the second IceBox.

Is your back aching from lugging endless sacks of soil, coco or other growth media in and out of your indoor garden? Then check out our latest blueprint, aptly named “The Water Room.” The idea is to grow monster tomato plants directly in a nutrient solution using a cutting-edge, modular Deep Water Culture (DWC) system called The Under Current™. But the liquid theme doesn’t end there. Water is also used to cool the garden using an ingenious chiller-based system created by Hydro Innovations.

Everest catches up with Dan and Stephen, the co-designers of this blueprint, to find out what logic exists beyond all this liquid!

GROWING IN WATER

Everest: Hi Dan. Let’s start by looking at the systems themselves. Am I right in thinking each 16 pot system requires both an air pump and a water pump?

Dan: That’s right, Everest. The inline water pump powers the negative solution displacement, which drives the Sub Current Culture (SCC) method. The linear, high efficiency air pumps provide the active aeration which supercharges the nutrient uptake.

Everest: So it runs 24/7 – even during the night cycle?

Dan: In properly aerated and balanced nutrient solution, plant roots can stay submerged 24/7, even through the dark cycle. Plants continue to metabolize nutrients and exchange gases in the dark, so keeping the solution moving aids in these processes. And remember, no timers for pumps means no worries!

Everest: How much solution is in each module?

Dan: We recommend an operating volume of approximately six gallons per module. That makes 100 gallons +/- in a 16XL (6 x 17 modules). A very small volume of solution is held in each joint (conduit) between the modules as well.

Everest: Is it the same for the bloom cycle?

Dan: We advise growers to drop the operating level to about four gallons per module during the fruit and flowering cycle. This helps ensure ample atmospheric oxygen uptake by the non submerged roots within the module. This oxygen exposure aids in proper fruit set and essential oil production as the plants mature. This technique can also mimic “drought conditions,” which triggers the plant to produce more oils as a means of reducing transpiration rates.

Everest: What about nutrient top-up?

Dan: The return module (epicenter) comes equipped with a high quality float valve built in for easy auto top-off. Each system also includes a bulkhead adapter for plumbing straight to your reservoir.

Everest: What about developing this set-up further with an auto-dosing system?

Dan: This system would work perfectly with an auto-doser like the Intellidose from AM. In this case you would plumb the Under Current (UC) float valve directly to a pure water source and let the Intellidose do the rest. Of course, you’ll need to set the doser to your specs, but then it’s on like Donkey Kong. The likelihood of a zero dump out run increases exponentially when a doser is used.

Everest: What EC should the top off res be balanced to?

Dan: When operated properly, top off should be balanced the same as the solution in the system. Traditionally hydro growers have been instructed to top off with half strength or pure water to avoid nutrient toxicity, but because the UC runs best with half strength nutes there is less of a chance of salt build-up. Ideally the solution in the system should stay balanced even as the plants use the nutrient and water. As a rule of thumb, if the nutrient EC/TDS rises as the solution is depleted you are likely running your levels too high to begin with. Conversely, if your EC/TDS drops it indicates you’ve started too low. Ultimately, as solution levels drop in the system the EC/TDS should stay stable; this is a good indicator that you’re dialed in. This EC/TDS stability will translate into improved plant health and greater pH stability to boot.

Everest: What if I experience drift in my nutes?

Dan: Correct it with your top off solutions. For example: a system started at 500ppm but has crept to 625ppm as the solution level has decreased. That’s a 25% increase, which can be easily offset by a top off res balanced at 25% below the initial 500ppm. This results in a top off res balanced at 375ppm to compensate. Ideally solution strength should stay constant as the plants consume it. This is a good indicator that minerals and water are being used at equal proportions.

Everest: What solution temperatures are optimal?

Dan: The system operates well anywhere from 65-80°F. We recommend maintaining a temperature between 68-72°F. This is a happy medium between optimum dissolved oxygen capacity and not chilling the nutrient solution so much that it slows the plant’s metabolism. If necessary, the water chiller can be easily adapted to the return pump.

Everest: Besides high water temps, what else can reduce dissolved oxygen levels in the system?

Dan: Elevated levels of dissolved solids can displace dissolved oxygen as they compete for real estate in the nutrient solution. So cool, half strength nutes are a perfect environment for high dissolved oxygen levels.

Everest: What dissolved oxygen levels should growers aim for in the UC?

Dan: We’ve tested on average +/- 9ppm of D.O. in solution. Water temps and quality will influence levels. As a point of reference, Dr. Elaine Ingham recommends no less than 6ppm to brew actively aerated teas.

Everest: You claim nutrient solution can last several weeks in the UC, but what about nutrient schedules that change by week?

Dan: Given that we encourage zero nutrient change outs, this does complicate things a bit. Best technique is to dilute any primary supplement into the top off reservoir.

Everest: How do you veg for the system?

Dan: Quad Tops are now available for the UC which allow up to four juvenile plants to be grown in each bucket. You can transplant our 5.5” heavy duty net pots right into your blooming UC rig. Other systems that veg well for the system include the GH Aeroflo2, AmHydro’s N.F.T., or transplant straight out of any aero cloner. Veg times in the UC are notoriously quick so start your fruiting cycles early to avoid overgrown madness. WE MEAN IT!

Everest: What grow media works best in the net pots?

Dan: Any non-wicking inert grow media tends to work best. Expanded clay pellets, growstones, silica stones, lava rock, sure to grow … to name a few. When using a wicking media like rockwool be sure to adjust the solution level to a point where it is not in contact with the media.

Everest: How much longer will nutrient stay viable vs. traditional ebb ‘n’ flow set-ups?

Dan: Time frames vary but typical change outs in E/F are about 7-10 days. In the UC, change outs should be necessary no sooner then 21-28 days. Many variables influence this time frame, so adjust your time frame to best meet your needs. Change nutes once they destabilize or become murky.

Everest: Is it a pain to clean in between crops?

Dan: Disassembly is not necessary. A bottle brush, green pad, biogreen and some elbow grease is all you need.

COOLING WITH WATER

Everest: Right, let’s talk about cooling this room with water. Many of our readers will be unfamiliar with using water chillers. Stephen, can you explain the basics of what a water chiller actually is and how it works?

Stephen: Sure thing. Firstly, water absorbs heat. And a water chiller cools water. So the basic idea is to use water to absorb heat from your indoor garden, and then a water chiller to get rid of it – similar to a regular air conditioner but with greater efficiency. A pump drives cool water through a manifold pipe and into a heat-exchanging device called an Icebox. The Icebox can be located on the exit duct of an air-cooled hood and provides increased surface area for the cool water to absorb heat from the hot air that passes over the grow lamps. The warm water then returns to the reservoir where it is re-chilled.

Everest: Why is water chilling more efficient than air conditioning?

Stephen: It’s down to the heat exchange capacity of water compared with air. The thermal conductivity of water is 23 times greater than that of air! A chiller will exchange the heat in a given space much more quickly than an air conditioner, allowing it to run less to get the same results. This is where you save electricity. With an air conditioner, air is passed over the evaporator instead of water. Since the air is less conductive, the evaporator can’t draw out as much heat as it can with water. The chiller evaporator is significantly smaller than an air evaporator because of the increased thermal load of water. In nearly all cases, the evaporator in a chiller will be significantly more efficient than that of an air conditioner, again allowing it to run less to get the same amount of cooling.

Everest: What type of chillers should be used?

Stephen: You need an industrial chiller – not a nutrient or aquarium chiller. Nutrient chillers might be more affordable, but they were not designed for battling against a constant source of heat! Only an industrial chiller is able to cope with constant loads and most can be placed outside if desired. Generally speaking, the larger your chiller, the more efficient it is.

Everest: How do you calculate the correct size of chiller for your room?

Stephen: Good question! Obviously this is really important to get right! First you need to decide whether you are going to use the water chiller simply for offsetting the heat generated by your grow lamps (i.e. keep your room at the same as the ambient temperature) or if you want to actively lower temperatures in your indoor garden further. It’s important to note that both heating and cooling are measured in BTUs (British Thermal Units). The first thing to do is measure how many BTUs are being generated from your equipment. In general, 1000 watt bulbs produce 4000 BTUs and 1000 watt digital ballasts produce around 2500s BTU of heat. (Exact figures vary.) That’s why ballasts should always be housed OUTSIDE of the garden.

Everest: So what sized chiller would this room need?

Stephen: 8 x 1000W lamps generate 32,000 BTUs. Each horse power of the chiller gives us around 12,000 BTUs. This room would need a 3HP chiller to cool the room entirely without A/C. Otherwise, a 3 ton A/C could be used in combination with a smaller (e.g. 2HP) chiller.

Everest: How is the cooling regulated / controlled?

Stephen: Cold water circulates around the system constantly. Regulation of the cooling effect is achieved through the fans that blow over the heat exchanger coils inside the Iceboxes. The fans are plugged into a thermostat controller. As it gets warmer, the fans speed up. As it gets colder, they slow down. The thermostat has a night and day setting.

Everest: Okay, now it’s time for the nitty gritty. I want to ask you about humidity. Surely cooling hot air rapidly through an Icebox creates condensation?

Stephen: A room full of transpiring plants is going to create humidity. Every indoor gardener has to deal with this and it’s easy to overcome with a dehumidier. As for condensation, the dew point changes with room temp and humidity levels. If you cool things down, water drops out of the air. Check out dew point calculators online. Typically, if you keep your humidity at below 50% then you will have no condensation.

Everest: How does the grower know how much the water needs to be chilled? I guess what I’m asking is, does the number of lights correlate to the water temp?

Stephen: Water temp is irrelevant to number of lights. You need to compare your water temperature with your room temperature. Assuming you have the right sized chiller, if the water temp is 10°F less than the room temp then you will maintain the room at that temperature. If you chill your water more than that it will create an A/C effect. 20°F difference will create active cooling in the room. It’s all about heat exchange and surface area, Everest, not just about how cold your water is. If you have three lights daisy-chained to just one Icebox, you can get the same results from three Iceboxes but you have to get your water a whole lot cooler. When you take away heat exchangers, you take away efficiency. But also, you need to take into account the volume of the room.

Everest: So you’re saying that a good rule of thumb is: the more Iceboxes (or heat exchange surface area), the better.

Stephen: You got it. The best efficiency is achieved when your water temperature is above the dew point and as close to your room temperature as possible.

Everest: Ok guys – that’ll do I think. I like the look of this room. Thanks for sharing!

What do you think of The Water Room? Have you used a similar set-up? Did Everest miss any questions? Post a comment below!

Last issue, Michael Christian discussed the fundamental fluid of a recirculating hydroponic system… water. Without pure clean water (low EC), we are going to be scratching our heads when it comes to troubleshooting problems when they occur. This time, we look at water analysis, maintaining nutrient balance and strategies for managing pH in a recirculating system.

Michael Christian is president of American Hydroponics, a hydroponic system designer, and consultant to commercial growers worldwide. Photos courtesy of AmHydro.

Let’s start with a very important question for every grower. Do you know what’s in your water? Have you ever had it analyzed? If not, it’s about time you did. Check out the Water Source Analysis chart to the right. If your water is above the limit on any of these elements, you will:

• require a custom nutrient formula that takes that element into account and compensates for it (you may need professional help with that)
• reverse osmosis to take your water to ideal and better (water treatment store)
• prepare for frequent reservoir dumps

This is a very basic source water analysis chart for most crops. Different plants can tolerate higher levels of certain elements like Sodium… others cannot. Sodium is not a plant food and will accumulate in a recirculating system. Very high calcium, over 150 ppm, is hard water and will require constant pH adjustment to keep pH down, a custom formula and/or frequent reservoir dumps.

If your water is coming from a well or a questionable ground source where there may be pathogens like E. coli, then request a coliform test also. Don’t risk it. You can use ozone (O3) to treat your source water. As long as ozone comes in contact with every drop of water you are guaranteed that all organic life forms get crisp. Your local high tech garden supply or water treatment supplier should have these ozonators and injectors.

Nutrient balance and pH

Assuming that your source water is A-OK, this next section is on understanding nutrient balance and pH, how to steer plant performance by manipulating EC at different stages of growth, and controlling pH fluctuations.

• Pure source water
• Balanced nutrient ions/anions (EC)
• Optimum pH
• Plentiful oxygen availability
• Optimum light/temp/humidity/air circulation/CO2

A Krubi plant (Amorphophallus titanum) which grows in Indonesia. It’s a tuber.This is what’s possible if all the basics are in line.

This article focuses on ‘inorganic’ nutrients: minerals derived from mineral salts*, which are primarily inorganic elements in the form of ions or ‘magnetically charged particles’ (the only form a plant can absorb anyway). These ions must be available (dissolved in water) for the roots to be able to absorb them by the process of osmosis. *High quality mineral salts are mined and processed, bagged, and sold as agricultural/solution grade with a guaranteed analysis.

It’s interesting to note that out of 2.2 lbs (1 kg) of plant material, 95% is water while 5% or 2 oz (50 grams) is dry matter. Of that 2 oz (50 grams), 95% of that is sugars and carbohydrates and only 5% or 0.08 oz (2.5 grams) are nutrient elements. Not a very large percentage? At these small weights, the balance and relationship of each element to one another is crucial for high performance plant growth.

Learning from Nature

When growing in soil, experienced growers know that by adding high quality organic materials to a loose arable soil, plants grow well and resist disease. Of course, the ‘good’ of the soil is the abundant microbial life contained therein. Microorganisms (fungi, bacteria and protozoa) are ceaselessly at work breaking down organic material by secreting enzymes and acids, consuming each other and releasing ions from their waste. It has been discovered that plants can spend 25% of their growing energy excreting exudates (sugars) to feed microbes, a fantastic symbiosis of Mother Nature. Microbes in turn feed the plant ions specific to the exudate. How cool is that? A healthy soil full of microbial life leaves no room for pathogenic microflora, pythium, fusarim, phytophera, etc. to colonize.

Often in hydroponics, specifically Nutrient Film Technique (NFT), Deep Flow Technique (DFT), aeroponics and any other strictly water culture system, this process is interrupted. Plants rely exclusively on ions being delivered in solution and readily assimilated by the roots AT WILL. Plants do not spend as much energy feeding or teasing microbes to colonize; instead they focus on growing, fruiting, flowering … fulfilling their genetics. Even in water culture, microbes will show up … and colonize the root systems. It’s inevitable. This is a good thing if they are fed copious amounts of oxygen.

When everything is dialed in, 40’ vines and 40 lbs of tomatoes per plant are not uncommon.

When using a media such as rockwool, perlite, coco, grow rocks, etc. and running inorganic nutrients, biology inevitably shows up as airborne fungi, bacteria, and spores that are brought in on entry vectors, bugs, friends, shoes, hair, etc. It has been discovered that microbes show up in as little as 24 hours after plants are introduced to a media based system. Plant roots know they’re there and will exude sugars to entice them to colonize. This all means that the inorganic nutrient solution that percolates through media arrives back at the reservoir with biology thriving. This is a good thing: it’s symbiotic, meaning there’s a healthy microbial population in a recirculating system naturally outcolonizing pathogenic microflora. This is a great reason NOT to disinfect a recirculating nutrient solution unless a variable goes radically out of balance and root die-off occurs, which attracts pathogens. In this case, enzymes would be the first line of defense to digest dead root material before active sterilization (hydrogen pyroxide or ultra violet).

40’ tomato vines from bato buckets with perlite media. 40 lbs of tomatoes per plant ... using a balanced nutrient formula, steering only by EC and biostimulants.

With media based systems if you are using a doser (highly recommended to keep EC and pH right on), be sure to compensate for the EC and pH at the root zone. You will find that the return solution to your nutrient reservoir likely has a higher EC. Take a reading of the leachate where the solution leaves the media. It is not uncommon to have nutrient running into rockwool at EC 2.2 and leachate at over EC 2.7 due to the concentration of salts in the rockwool. If EC 2.2 is the target, lower the incoming EC to 1.8. Keep an eye on this discrepancy as you will want the duration of your feed cycle long enough to flush out accumulated salts … usually 10-20% runoff back to the nutrient reservoir for top feed irrigation. Shorter irrigation cycles during the fruiting flowering cycle (creating a ‘just moist’ media) forces roots to dry out more, which increases osmotic pressure. This triggers plants to speed up the fruiting flowering process.

Doser set up - standard fare for high performance recirculating systems. Sample pot at right with probes measuring pH & EC. Peristaltic pumps middle bottom pumping nutrients on demand to nutrient reservoir. CF 18, pH 6.3, water temp 72ºF.

With either method, measuring conductivity of the nutrient solution is critical. The universally accepted method is EC. The EC test is a measurement of the electrical conductivity of water. Pure water (with no dissolved minerals) does not conduct electricity, so the EC is 0 (EC 0.0), but as mineral salts are dissolved into water the electrical conductivity increases.

We can use this to our advantage when growing plants: if the plants remove minerals from the nutrient, the EC value falls, so we add more minerals. If the plants remove only water from the system (on a hot day, for example), we only have to add water, as the EC value will rise. That’s why a float valve is so important, as well as a doser to manage these fluctuations automatically.

EC, CF vs ppm: Which is a more accurate measurement of nutrient strength?

It’s common knowledge that 1 ppm is the same as 1 mg/ liter or 1 gram of nutrient in 1 million grams of water. The universal method of measuring the strength of a nutrient solution (where anyone in any country will be speaking the same language) is Electrical Conductivity (EC) or (CF) which is really EC with the decimal point moved one digit to the right. For example: 0.8 EC = 8 CF. Stating the solution strength in ppms, (which many growers do) can be misleading, as different salts may weigh the same but have different ppms when dissolved in water. The ppm measurement actually came from waste water treatment or TDS (total dissolved solids), where there are several conversion factors where 1 EC equals either 600 ppm, 640 ppm, 700 ppm, or 750 ppm. So which one is which? Very iffy. Good luck if you stick with ppm!

EC is important to plants because a solution that is too strong can burn the roots and causes reverse osmosis. Osmosis is the natural process whereby water, including dissolved minerals but not solids, is moved through a semi-permeable membrane, such as the cell walls in plant roots: the weaker solution flows to the stronger. This is how plants take in minerals. However, reverse osmosis occurs when solution is drawn out of the roots because the solution on the outside of the roots is stronger than on the inside: this leads quickly to plant death. If you’re not measuring correctly or not calibrating your meter often, this could sneak up on you… such a simple variable to control. Get a good meter or a doser.

One tank, one doser, 10,000 plants. This grower purges 50% once a month.

EC levels are different for many crops, even at different stages of growth of the same plant. Lettuces like ECs around 0.6-1, tomatoes: 2-4, fast growing flowering annuals: 1.2-2. Different plants, depending on their genetic history (i.e. where they came from) are used to growing in native soils that exert a unique pressure on the roots: clay, loamy, dry, wet, and so on. Drier climate plants can take a higher EC than tropical plants in vegetative and flowering growth. But the rule of thumb is: The lower the EC, the more loose (vegetative) the growth; the higher the EC, the tighter, more compact, the growth.

Ultimately, experience with your plants will tell you what EC levels they prefer. If your plants are thin and leggy, and provided there is sufficient light, then the EC level may be too low and you need to raise it a couple tenths at a time. Observe plant response. If your plants are short, thick and stunted with sufficient light, then the EC level may be too high: back it off a couple tenths. This is one method by which you can steer plant performance on a fundamental level. Vegetative growth uses a lower EC, while flowering growth uses a higher EC as a rule. Many high phosphorus (P/K) or mineral salt amendments actually create higher EC in the nutrient solution. If you hadn’t added them and just increased the EC, you would most likely get similar results. Plants will take what they want. Keep the solutions balanced.

Of course, everything stated in the previous paragraph is all predicated on satisfactory transpiration rates, which will be covered next time. Transpiration makes nutrient absorption possible. If you don’t have fresh air movement and ambient or injected CO2 available at all times, or if humidity is too high, EC manipulation is not going to make much of a difference.

Getting to Grips with Nutrient Deficiencies

It’s important to understand how the elements work…especially Calcium and Nitrogen. Deficiencies in either one can be easily detected and corrected.

Calcium is a non-mobile element, critical for building strong cell walls as well as activating enzymes that push auxins into new growing tissue. Calcium must be constantly supplied from roots to new tissue. If humidity is too high (90% and up), plants stress as they cannot transpire and Calcium does not get to meristems (growing tips) and tender shoots, resulting in tip burn, leaf curl, blossom drop, and so on. You will see a dried out look in new tissue as cells have collapsed. No bueno.

Whereas Nitrogen is a mobile element. If a plant cannot absorb enough Nitrogen through its roots, Nitrogen will be drawn from the lower leaves along with chlorophyll to newer, higher priority growth. Once again, if there is adequate Nitrogen in solution and humidity is too high, transpiration will be low and Nitrogen, instead of being drawn up from the roots, will be drawn from the low priority growth: older leaves. It’s a matter of survival priority how a plant steers its course under stress. If your plants are thin and leggy, and provided there is sufficient light, then the EC level may be too low and you need to raise it a couple tenths at a time. A plant’s top priority is developing a flower to reproduce, second is shoot and leaf development, and last is root. Roots will die off first, leaf and shoot second, flower last.

Nutrients

I’ve found that the highest quality mineral salt based nutrients in the market, powders and/or liquids, all work. The most reliable ones have been around the longest, because they are CONSISTENT and EASY TO USE. They all appear fairly well balanced among the elements and will grow plants well. We’ve used most of them with good results. Of course, good nutrient availability depends on the water the nutrients are mixed into … but you know about that.

The large commercial operations we work with use 2-part powder (dry) nutrients and add water to make their own stock (concentrated) nutrient solutions. Buying liquid nutrients is not cost effective at the volumes they use; they will not pay extra dollars for shipping water, which makes sense. Eventually they may create their own formulas on site.

Mixing Your Own Nutrients

Two-part dry nutrients typically are used like this: In two 10-gallon containers filled with pure (preferably warm) water, dump one part (Bag A, pre-weighed) in one container, and another part (Bag B, pre-weighed) in the second container. Bag A has Calcium Nitrate, Potassium Nitrate and sometimes Iron. Bag B has Potassium Nitrate, Magnesium Sulfate, MKPhosphate, etc. and all the micros carefully measured. Bags A and B are equal in weight. Stir thoroughly until salts are totally dissolved. The reason they are not mixed together in one container at those concentrations without being chelated is that Calcium would react with Sulfur and Phosphorus making Calcium Sulfate and Calcium Phosphate… AND drop out of solutions as a precipitate. No bueno.

Sediments that fall to the bottom of the containers are inert carriers with no consequence to the purity of the stock solutions. To use the stock solutions: pour equal parts of A and B into the nutrient tank to the desired EC and adjust pH slowly to pH 6. Viola, a balanced nutrient solution on the cheap. That’s how it’s done in the commercial growing arena.

When choosing a nutrient to use, if you buy liquids, the manufacturer does all this for you, no mess no fuss, but then you pay for that convenience. If you have friends or associates who recommend a nutrient because it is producing good results for them, you may want to go with that. It’s usually best to start at a level that is known to be effective and recommended by a trusted companion grower. If you go to a hydro shop and the owner doesn’t have any growing plants or the plants he/she does have look stressed and sick, it may not be wise to take the owner’s recommendations as you have no evidence he knows what he’s talking about. Good luck if you do.

We always have our commercial growers test source water, add nutrients, and then test that fresh nutrient solution. After two weeks we test the nutrient solution again as well as a plant tissue analysis. We can tell exactly what the plant is taking up and what is accumulating in the nutrient solution. Then we reformulate the nutrient to compensate for any element that is out of balance in the solution with the demand of the plant. In this way a nutrient solution can be recirculated for a month or longer depending on the size of tank and use of a nutrient doser.

For small commercial or hobby growers, it is not practical to fine tune the nutrient to this level. Since every growing environment is different, ultimately we have to know our plants and be able to read them: this takes at least three or four cycles, each time learning from the last. (Actually, it takes a lifetime and still things happen that keep us scratching our heads!) When experimenting, make small adjustments in nutrient… or try bio stimulants, which assist the natural plant processes without affecting the nutrient balance significantly. Plants like consistency, no big swings in EC or pH, a balanced nutrient solution, and stable water temp – especially when you are refreshing the solution and use super cold water on roots after they’re used to warm.

pH

pH is the acidity or alkalinity of the nutrient solution. It is a measurement of activity of dissolved hydrogen ions. They are most active in the zone where all the elements remain in solution and available for plant uptake.

Plants can survive in the pH range 4.0 to 8.0. Below 4 there is a danger of the roots being burnt and some minerals are not available to plants. Above 8.0 some of the minerals can be precipitated or are not available to the plants. If roots are ever exposed to extremely low or high pH, turn off irrigation, bleed 50% of the tank, add fresh water, get pH spot on and then turn irrigation back on. Most times you can save a crop with this method.

The most important thing to remember is to keep pH between 5.5 and 6.5. Aim for 6. All the elements are available in that range. When plants are growing in good light and warm conditions, the normal trend is for the pH to rise and we have to add a pH lower (acid solution). In cool, dark, short day conditions, it can be normal for the pH level to fall and we have to raise the pH with pH raise (alkali solution). As a rule, as plants feed, their root waste (sometimes in the form of ethylene gas) is basic and raises pH. In media based systems, microbes eat most of this up so pH is fairly stable. In water culture, root exudates raise pH, making the addition of phosphoric acid a regular occurrence.

With the addition of either phosphoric acid, pH down (try to stay away from sulfuric acid as it accumulates Sulfur and takes up precious EC) or Potassium Hydroxide, pH up. Always mix with water at least 100 to 1 before adding to solution. Adding pH adjuster full strength causes all kinds of mischief in the nutrient solution. Elements exposed to a pH below 4 (even temporarily) may precipitate and you won’t know it until a deficiency shows up: even then you won’t know what caused it. Be careful. If possible use a pH doser to incrementally dose on demand. In this way you avoid spikes in pH.

As adjuster is added to nutrient solution, either phosphorus or potassium is being added. It does affect the nutrient balance. Custom formulated nutrients can take that into account, but if your tank is big enough, that is enough to mitigate the problem by sheer volume.

When all else fails and you are having performance problems with your plants, having checked off every other variable, the last being your nutrient tank, purge your tank. Drain off 25 or 50%, top up water, use fresh nutrient, adjust pH and see how that goes. If you normally use a consistent amount of pH adjuster daily and all of a sudden the nutrient is not demanding adjustment anymore, you can bet your solution is out of balance and needs to be purged or dumped. As you go though complete growing cycles, you will begin to see the signs and patterns.

If plants lose their sheen or start cupping leaves and if EC and pH are right on, then there’s a strong possibility the nutrient is out of balance and plants are either hungry or toxic. Purge or dump the tank. Resist the temptation to add something else to the solution. Better instead to check transpiration rates, light, temp, relative humidity, CO2 and air movement.

Ok that will do for now! Next time we will look at the last of the five basics – plentiful oxygen availability and optimum light/temp/humidity/air circulation/CO2.

Are we answering all your questions? Tell us when we hit the mark or when we don’t! Leave a comment below and help us to help you!

The winter time is when indoor gardening shines. Bright lights, CO2, and enclosed spaces all make for a potentially hot environment for any plant. Some plants thrive in hot environments. Most do not. Winter is when the outdoor ambient temperatures help reduce, depending on your location, the effect of those heat factors.

Winter is one season in four. For the rest of the seasons, you may need to cool your environment. If you don’t, you risk lower yields and heat stressing your plants. Or, you must limit yourself to hot-thriving species.

Two kinds of cooling exist today for grow rooms: ambient air cooling and liquid water cooling. Ambient air cooling requires an air conditioner and ventilation to exhaust the hot air from the grow room. Water cooling requires the same and focuses on providing a cold solution near the heat source (typically, the grow light). Where air cooling pushes cold air to every aspect of the grow area, water cooling targets just the heat-producing areas of your grow area (typically, your light and reflector).

Let’s talk about Hydro Innovations’ ChillKing & Ice Box. The ChillKing is Hydro Innovation’s liquid chiller solution. I received both the 1/2 HP ChillKing and Ice Box at the beginning of the summer growing season.

Ideal temps for indoor gardening are an ambient 72-75 degrees Fahrenheit. Every grow room maintains different ambient temperatures. My grow room, in the summer, runs as hot as 100 degrees Fahrenheit. Talk about plant heat stress.

That was, until I installed a 1/2 HP ChillKing and a 6″ IceBox from Hydro Innovations.

Hydro Innovations offers their ChillKing in 1/2 HP through industrial-engorging 10 HP. The IceBox is available in 6″ ducting and 8″ ducting sizes.

The ChillKing is a essentially an air conditioner with liquid cooling plumbing for the water path. On the side of the ChillKing is an electronic temperature control which will power on the unit—thus cooling—when the water flowing through its input/output flows in above the temperature set by you.

The 1/2 ChillKing can either be mounted through a wall or window sill (as with traditional window A/C units). I used an 1800 gph submersible pump and 35 gal water reservoir for my cooling. With the ChillKing, I believe that you could use an even smaller water reservoir (25 gals even) for chilling–depending on your lighting setup. The cold water response from the ChillKing is near flash-instant, from hot water to cold.

This unit is completely different from the cheap plastic units currently available. The ChillKing is built like a brick s***house. Not a single cheap component. Metal components throughout and metal hose connectors.

My only suggestion for improvement for the ChillKing would be at the hose-connections.  Instead of screw-on, fixed hose connectors on the unit, I would like to see garden-hose free-spinning connectors or even quick-connectors.  Without this, once you connect your water lines, you may be twisting the entire hose to manipulate it onto its receiving connectors (water reservoir connection, pump connection, IceBox or Fresca Del Sol connections, etc…).  Depending on your setup, this can be a pain.

Add the IceBox.

With a 6″ IceBox and a 440CFM 6″ Can-Fan fan connected to my 600W light and reflector, the pair worked wonderfully! The temperature dropped dramatically from summer months scorching my grow chamber. My grow chamber dropped from 100 degrees F day / 85 degrees F night to 74 F day / 70 F night. Previous to installing this, I had to focus on temperature resilient and heat-thriving plants. After implementing this setup, the plant kingdom is my oyster and I will grow what I want.

However, the ChillKing & 6″ IceBox could not and cannot drop my grow chamber temperature below 68 degrees even with the light off (flowering darkness). If you’re a grower who needs to drop their lights-off flowering below that temperature (some growers would like to hit around 60 degrees F), I would recommend stepping up to an 8″ reflector and the 8″ IceBox for more CFM air flow.

Worm-gear clamps cinching the connections to the IceBox.

My only improvement suggestion for the IceBox is the same as for the ChillKing—quick connect connectors. I had to wrap tape around the input/output connectors and cinch the connections water-tight with small worm-gear clamps. Especially useful would be quick-connections which would also retain the water in the hose when removed from the IceBox. Otherwise, moving/reconfiguring the IceBox will lead to a watery mess.

The ChillKing and IceBox allowed me to increase my yields, avoid heat stress, AND expand the types of plants which I can grow. I will not return to a chiller-free setup.

In case you missed them, Hydro Innovations offered complete setup deals (chiller, hoses, IceBox, water reservoirs, and and everything you would need) across this past summer. Look for their current pricing and any promotions at: http://www.icehousedistribution.com/.

NOTE: please read Part 2 for the update, which corrects the set-up mistakes made here.

Please note: blog posts are the opinions of independent growers, and do not necessarily reflect the opinions of Urban Garden Magazine or its affiliates.