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Who’s Afraid of Hydroponics?
Posted By Urban Garden Magazine On November 6, 2009 @ 4:14 pm In Beginners | 1 Comment
Hydroponics is the science of growing plants without soil. Plants grown in hydroponic systems will develop faster and they tend to produce higher yields. As a result, hydroponics is used extensively in commercial agriculture.
But what about a hydroponics set-up in your home? Does the idea of growing your favorite plants in a hydro system seem a bit high-tech or alien to you? Or do you harbor misgivings about growing plants in anything other than good old-fashioned dirt?
We challenged Jordan Weiss, a proud exponent of hydroponics, to break down some of the common barriers that exist between soil lovers and hydroponics.
Hydroponics in a Nutshell
The word “Hydroponics” comes from Greek, “hydro-ponos”. Literally it can be translated as “water (hydro) at work”. So what “work” is the water doing? Well, as it happens, quite a lot! Hydroponic plants are not grown in soil. Instead all the nutrients they need are supplied directly from the water. This is achieved by first dissolving special hydroponic nutrients into the water – the resulting “mix” is often referred to as a nutrient solution. It contains all the essential food in a directly accessible form. This allows hydroponic plants to put less energy into creating root systems (as all the food they need is right there) and more energy into fruits and flowers!
Barrier 1 – Hydroponics is way too complicated.
“I’m just an everyday gardener. Just give me plain old pots and soil! Hydroponics is too technical and difficult for most people to get to grips with! It involves too many expensive parts, pieces and gadgets and things can easily go wrong. Also, there’s a bewildering choice of system options and too many decisions to make!”
Hydroponics is quite simple with a little thought and a realistic plan for your growing goals. It’s simply the science or craft of growing plants without soil. That’s all. It’s about growing plants with water, thereby providing complete access to the nutrients and additives in your solutions. The environment (temperature, humidity, and CO2) is the same in hydro or soil, so this is not an additional concern related to running a hydro system.
There are four basic systems from which to choose: Aeroponics, Ebb and Flow, Deep Water Culture (DWC) and Drip. Beginners should avoid Aeroponics as the margin for error is a lot tighter, which reduces your options to three. Once a system is selected, a grower just needs to understand the relevant components at play. Usually these consist of a tray, reservoir and, depending on the chosen system, a pump and a timer.
Regularly test the pH of your nutrient solution using a digital pH pen or a manual test kit. Both are available very cheaply at your hydro store. You should drain and clean your nutrient reservoir regularly – ideally once a week, especially important as your plants mature.
Barrier 2 – If things go wrong in hydro, you can lose your whole crop.
“If a pump fails, all my plants could die within a day, even hours! Soil is far more forgiving than hydroponics.”
Hydroponics gives the grower ultimate control over their plants’ nutrition. The observant grower can respond to subtle changes in the appearance of their plants almost instantaneously. But that greater precision in control comes with a decreased tolerance for neglect. In most hydro-based systems you can lose the crop rather quickly if things go seriously awry. I don’t mean to be alarmist, just realistic! There are limited factors that can go wrong and they are readily avoidable.
If your environment is correctly adjusted (temperature, humidity, CO2 and air flow), then the two most common problems associated with hydro-based systems are: nutrient deficiency due to incorrect pH levels and pump failure (resulting in plants not getting water.)
In hydroponics, pH is king! For most plants, it’s vital to maintain a relative zone of 5.8-6.1 at all times. pH governs which nutrients can be absorbed, and at what rate. If reservoir pH is off, even a perfect nutrient solution will contain elements that are “unavailable” to the plants for uptake. A small pH change in a hydro-based system is very important as far as your plants are concerned. The pH scale is exponential, so don’t think for one minute that a 0.1 shift in pH isn’t a big deal – it is! pH can be thought of as a “door” between the root zone and the nutrients. If your pH swings out of range, you are effectively locking that food away from your plants. Check and adjust your pH daily.
Tip: Fulvic acid, allows for a greater range of pH fluctuation across the board by making nutrients available over a broader spectrum of pH zones.
Pump failure also poses a real threat to a hydroponic system – especially when using non-restrictive mediums that can dry out quickly, such as clay pebbles or grow rocks. It is imperative to check your plants daily for proper moisture. Some hydroponic growers prefer to use rockwool or coco coir as a growing medium. These retain more water and allow therefore afford the grower a wider margin for error should a pump malfunction occur. Some hydroponic systems work using multiple pumps as a fail-safe.
Barrier 3 – Hydroponic produce doesn’t taste or smell as good as soil-grown produce.
This is a contentious area so let’s tread carefully! While it can be more challenging to achieve a full-bodied taste and aroma from a hydroponics based grow, it can be done. Some crops are undeniably more suited to hydroponics than others. Keep in mind that it is significantly easier to get a vastly LARGER YIELD from hydro than soil! Now while some veteran soil growers will contest that they can match the yields in hydro, veteran hydro growers can certainly produce crops with as much aroma and taste as soil. It really comes down to experience. If you are shooting for yields first, it’s easier for a keen beginner to achieve more production out of a hydro-based system than from soil.
So how do you get the best taste and aroma from a hydroponics system? First you have to start with great plant genetics. After all, everything starts in the genes! You need to find a variety that is known for yielding fruits or flowers noted for their smell or taste. Then, consider adding organic elements to your hydro system, you can create the same robust full-bodied flavors associated with soil grown plants. A grower will need to use humic acids, guanos, kelp extracts, amino acids and microbes to create that craftsman quality flavor.
Barrier 4 – Hydroponic produce is full of chemicals.
This is a common misconception. First off, what chemicals? Nutrients come in all shapes and sizes these days. Growers today can certainly grow purely organic in hydroponics – a technique known as “bioponics.” What are disparagingly referred to as “chemical fertilizers” are usually made from food grade minerals, which are simply purified elements. These are the same elements that come from the ground, rocks or dead organisms. The only thing that makes them “unnatural” is that chemical chelators are used in some hydroponics solutions to facilitate the absorption of minerals and to enable minerals to remain in the solution bottle without interacting with other minerals in order to avoid unwanted precipitates. These chelators are all food-grade and are used in most foods we eat daily. There are a wide range of organic and semi-organic products that use chelators in very low dosages or use only humic, fulvic, and amino devices (organic based chelation) to help preserve nutrients in solution and make them more readily available to plants.
Many growers (using both soil and hydroponics) improve the taste of their crops by watering with pure water during the final week or two before harvesting. This is a technique known as “flushing”. And guess what? Flushing your crop is a whole lot easier in hydro!
Barrier 5 – Hydroponic produce is less nutritious than organic.
If you feed your food well, it will feed you well. Food grown in hydroponic systems with the correct availability of nutrients will, in turn, contain as much nutrition as organic produce.
Barrier 6 – Root systems don’t thrive in hydroponics.
Root systems tend to be smaller in hydroponics, but that’s because the roots don’t have to do as much work! All the water, nutrients and oxygen are right there in a well-designed hydroponics system. Sterile hydroponic conditions can lack beneficial microbes that protect and nurture the root zone. But this can easily be overcome.
Hydroponics was conceived as a means to provide roots maximum aeration and nutrient uptake capabilities by bypassing the buffers and mediators found in soil. Nutrients are available in directly accessible form. They do not need to be “broken down” as in organics. Early hydroponics focused on sterility; ensuring “clean” nutrient solutions were devoid of any organisms (pathogenic or beneficial). However, researchers experienced difficulty in finding a good sterilizing (oxidizing) agent that wouldn’t also damage the root system. Early hydroponics pioneers didn’t realize that water temperature greatly affected the relative dissolved oxygen levels held within the water. Water at cooler temperatures holds the requisite oxygen levels in which plants thrive and also deters more pathogenic anaerobic (non-Oxygen loving) microbe growth. Today’s hydroponicists now use water chillers, oxygenators, beneficial microbe solutions and specific hormones to keep roots brilliantly healthy through an entire grow cycle – creating root systems just a strong as those found in the best soil mixes.
Barrier 7 – Hydroponics isn’t organic.
Yes it can be! There are a plethora of different organic-based hydroponic nutrients and additives as well as organic-based mediums that enable growers to produce completely organic hydroponic crops. Remember, any medium that doesn’t employ soil is essentially a hydroponically-based medium as you are relying on the water to do the work of carrying the plant food. Coconut coir based products are a firm favorite with hydroponic growers. They hold onto organic materials such as humates and slowly release them back to the plant for increased flavor and aroma. Perlite and vermiculite-based mediums are also hydroponic and all natural. Rockwool, another popular hydroponic growing medium, is also derived from completely natural sources.
Barrier 8 – You cannot use the “drain-to-waste” method in hydroponics.
Yes you can. Hydroponics doesn’t require a recirculation-based system. While recirculation-based systems offer increased water and nutrient efficiency “drain-to-waste” based systems boast extreme resistance to infection. Many soil growers don’t realize that their systems are already “drain to waste”. They either hand-water with a one gallon jug or use a trashcan with a pump and rain wand to feed their plants every other day. Hydroponics can be set up the same way. (These systems are sometimes referred to as “passive.”) An essential component of any passive hydroponic set-up is a growth medium that holds water for at least a day such as rockwool or coco coir. That same watering wand or a drip system can be used to deliver the nutrient solution in a passive hydroponic setup. Instead of returning to a central reservoir, the “run-off” drains out of the system or into a separate reservoir below. Some growers prefer drain-to-waste systems because if one plant gets infected by a disease, the spores from this infected plant are not reused in the main reservoir, which risks infecting the entire crop. Thus, in a drain-to-waste system, the diseased plant can be treated independently with minimal chance of it infecting other plants. Also, with drain-to-waste systems plants always get fresh nutrient solution and can also be drenched or fully flushed.
Some growers build hybrid systems. They recirculate the nutrient solution when the plants are young and their nutrient and water requirements are relatively low and, when their plants are more mature and heavily feeding, they switch to drain-to-waste.
Barrier 9 – Hydro systems are expensive.
This is a major misconception. Often, people think of hydroponics as extravagant aeroponic systems loaded with PVC, white plastic, specialty fittings, etc. The truth is that a great hydro setup can be built on a shoestring budget. It’s all about the tray and the pump. Those are the two big expenses – and they’re not even that expensive! I highly recommend purchasing a tray with good drainage “lanes” built into it. (This is a tray that has been specially molded to maximize drainage.) Then obtain a pump large enough to run your system. A simple, cheap rubber-maid storage bin works great as a reservoir and can be purchased at a hardware store for under twenty bucks. Hell, that’s how I started! Your choice of media is also important (common choices include rockwool, coco, and clay pebbles), a working pump (don’t skimp on that), and a good watering schedule that’s dialed into the absorbency of your choice of growth media (the more absorbent your growth media is, the less frequently it needs to be irrigated.)
It’s absolutely not about spending an exorbitant amount of money!
Barrier 10 – All my friends are growing in soil, so I should too.
Growers learn from other growers. But just because someone you know is doing soil, it doesn’t mean that it’s the best medium for you, or anybody else! Over the last ten years soil has experienced a large resurgence due to vastly improved new mixes. These mixes boast increased aeration, they are made from better sources of organic materials (guanos, castings, fish, blood and bone meals, etc.) and employ other specialty ingredients to increase growth, flavor and aroma. However, a good hydro grow will still give most growers a larger yield and, when done properly, just as much flavor and aroma as any soil grow. Taking this into consideration, it could greatly benefit you to go against the grain and rock that hydro! Dare to be a little different and don’t be afraid to be a pioneer!
Okay – so, why hydro?
The advantages of hydroponics include:
Jordan Weiss is a founding owner of GreenCoast Hydroponics in Santa Barbara, Long Beach, Orange and Whittier. www.gchydro.com 
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