Life is a miracle and cultivating plants is part of that miracle. In caring for our plants we form a symbiotic relationship with them. We watch our plants grow and do everything we can to help them reach their full potential. When we harvest and consume our crops, those same plants we cared for help us to grow! Seasoned gardeners are aware that this is just one relationship, one link in the miraculous chain of life. It’s so marvelous that many beginner gardeners focus exclusively on that ‘link’ – maybe because it’s the one that happens to be most directly appreciable to our senses. But there is a whole universe right beneath our noses that exists just beyond our powers of vision. It is a hidden world of microbiology that exists in the soil itself. We tend to appreciate this indirectly through effects, rather than causes, observing a plant as “healthy” or “diseased.” But with a little knowledge, seasoned with some imagination (or a powerful microscope!) the true extent to which we share this world can be revealed and the way in which we care for our plants is transformed.

A World In A Teaspoon

Okay, enough romantic talk of Mother Nature. Let’s move on to some mind-blowing facts. And these facts really are mind-blowing! Don’t just “uhuh” as you read these. See if you can actually visualize what is about to be described:

Imagine taking a teaspoon and dipping it into some living soil. Lift it up and hold it in front of you. What do you see? A teaspoon of dirt?

A teaspoon of living soil contains 100 million to 1 billion bacteria, 1 to 40 miles of fungal hyphae, and 1,000-100,000 protozoa!

40 miles of fungal hyphae in one teaspoon!? Now do you see we’re talking about another world within our world? What are these organisms? Well, they are all part of this whole chain of life that helps to grow your plants. These organisms are as real as they are small. And in their huge numbers, they play a really important role in plant health and growth. The bacteria eat the exudates (simple sugars, carbons, carbohydrates) that the plant puts out through its roots, which are then eaten by the protozoa. What is excreted by the protozoa is now plant-available nutrients. Beneficial fungi protect the plant from pathogens and harmful microbes, as well as creating pathways in the soil that bring water and nutrients back to the plant from larger distances. Bacteria and fungi work together in decomposing organic material and making the nutrients plant-available. This is a sustainable process known as “nutrient cycling” that allows for the growth of healthy plants, without the need for fertilizers, pesticides, and other chemicals. After all, there’s no one out there putting Miracle-Gro on our rainforests each year, yet look at how successful plants are at growing in these microbial-rich environments!

The War on Terra

Most soil these days lacks the biology necessary to cycle nutrients to the plant and protect it. Where did they go? They were killed off by so-called modern agricultural methods or “the war on terra” – years of abuse including overuse of synthetic fertilizers, pesticides, fungicides, over-tilling, and compaction.

Chemical fertilizers and other -cides contain salts. Remember back to high school science where you learned about the process of osmosis? It’s the movement of water through a cell membrane from a solution of low solute concentration to a solution with high solute concentration. In living soil, water is locked up in the cells of the microorganisms. With the proper biology in place, you can cut back on your watering by up to 30%! When salts in the form of chemical inputs are added to the soil, the water is drawn out of the microbes and they are either killed or go into a dormant state. Now the plant is dependent on you to provide all of its food and protection. That’s why you have to fertilize on a regular basis.

In addition to damaging the biology in the soils, these chemicals are having other impacts of much greater consequence. Nitrates from fertilizers are leaching into our water system, and pesticide exposure has been linked to a variety of serious diseases such as cancer. There’s a reason that lawn companies recommend keeping children and pets off lawns after they’ve been sprayed. These chemicals are highly toxic!

So what’s the alternative? There is a shift from our current N-P-K paradigm towards an organic way of gardening by feeding the microbes in the soil and letting them do the work for us. Our ancient ancestors gardened in this manner long before we knew what bacteria were! Fertilizer was in the form of manures, which were decomposed by the microbes and provided all the nutrients the plant needed.

Creating Life in Soil Again: Compost Tea

Using present day technology, we are now able to add these beneficial organisms back into our soils and feed them through a variety of organic inputs. The three best things you can do for your soil is to top dress with compost, mulches, and compost tea. Since many of you probably already know about the benefits of compost and mulch, I’d like to focus a bit more on compost tea.

When I say compost tea, I’m referring to actively aerated compost tea, or AACT for short. This distinction is important because there is a big difference between throwing some compost or manure in a bucket and letting it sit for a couple of weeks, and AACT.

AACT is an aerobic water solution that has extracted the microbe population from compost along with its nutrients. The concept behind compost tea is quite simple, though the actual process becomes scientific and has many variables that need to be accounted for. The idea is that compost (full of beneficial microorganisms) is put into water and then nutrients or foods for the microorganisms are added to allow the bacteria and protozoa to multiply rapidly and the fungi to grow. Air is sent through the water to keep the dissolved oxygen levels above 6 mg/liter, as this selects for the aerobic microorganisms, which are the ones found to be most beneficial. At the end of the brewing cycle, what you have is a concentrated liquid literally teeming with billions of microorganisms that can be sprayed directly onto the leaf surface of your plants or onto your soil. This puts the “good” biology where the plant needs it to protect itself. It keeps the plant healthier and helps to fight off potential diseases. The “good” biology occupies the infection sites on the leaf surface and survives by consuming the exudates that the plant puts out. The “good” biology then out-competes the pathogens for the space on the leaf surface or around the roots (rhizosphere). This is how plants protect themselves and thrive in nature.

It is possible to make bad AACT. If you don’t start with good compost, don’t add the proper amount of nutrients, or keep the brew sufficiently aerated, you could be selecting for pathogens rather than beneficial microbes and end up with a tea that will have little to no effect on your plant or possibly even do damage.

Along with compost tea it’s important to do applications of other bio-amendments such as soluble seaweed, humic acids, and fish hydrolysate, for example. Seaweed serves as a bacterial food substrate and also provides additional benefits for your plants in the form of growth hormones, increased stress resistance, and faster plant response. Humic acids serve as a fungal food, and also chelate (bond with) minerals in your soil and make them available (many minerals in your soils are “locked up” or unavailable). These sorts of applications work by feeding the microbes, which in turn feed your plants.

When gardening in this manner, it’s important to adjust your application rates or program to fit within the needs of your garden. I’d suggest an initial topdressing of your garden with compost and an application of compost tea, adding soluble seaweed and humic acids to the tea after brewing. Then, another application 2-3 weeks before planting and another one when you plant your starters (adding mycorrhizal fungi into the hole at this time). In the fall, I’d add a mulch to your garden, followed by an application of compost tea (to speed up decomposition over the winter). You may or may not need an organic fertilizer (NPK below 10-10-10) to supplement the rest of your program.

Once an organic program has been established, typical application rates of AACT, humic acids, and seaweed are only 3-5 times per year. Now the plant is in charge, and the organisms are in place to cycle the nutrients for the plant. This is what sustainable gardening is all about!

WORDS: Tad Hussey, Keep It Simple, Inc. www.simplici-tea.com

THE BASICS

What is a Soil Amendment?

A soil amendment is just stuff you add to soil – either a single ingredient or a blend – to help combat micronutrient deficiencies, adjust pH, combat salts, introduce microbial activities, and so much more. But hey, don’t confuse soil amendments with fertilizers – these add formulated food for the purpose of the plant, while soil amendments are used to treat the soil itself. However, that said, many soil amendments are also used in blended fertilizers and provide feeding nutrition.

Types of Amendments

Soil amendments come in many different forms; most are organic, which is preferable for your soils, some are considered “natural” which are derived naturally though not necessarily organic, and some are synthetic. Organic amendments as well as naturally derived amendments are the best way to change your soils from a dead clay heap to a living, symbiotic organism. The categories of amendments include: bark products, plant byproducts, animal byproducts, manure-based, compost and mulch based, and rock and mineral powder based.

Do I Need a Soil Amendment?

As a rule of thumb, all soils love to be amended; the question actually lies in: which amendment do you need? It is best to have your soil tested for pH, micro nutrient deficiencies, salt content and more before applying products that will alter the nutrient value of your soil. Just because lime is a great amendment, it does not necessarily mean that you need it. When selecting a soil amendment you look for how long the amendment will last in the soil depending on your growing season; the soil texture and salinity; the plants you are planting; and the salt and pH content.

Which Amendment is Right for Me?

PLANT BYPRODUCTS

First, let’s take a look at the soil amendments that are made from plants:

Alfalfa Meal

Feeds with 3% nitrogen and is known to contain growth factors and mineral content. Very common ingredient in many blended organic fertilizers.

Coconut Fiber

Great aerator. Excellent soil amendment or a standalone grow medium. Coconut not only provides great aeration but also efficient transfer of nutrients. Check your source though, as coconut can be very salty and this can harm soils and plants.

Cottonseed Meal

Nitrogen super booster! (Between 6-7%.) Only “organic” if it was grown that way – most cotton farms use chemical foods and insecticides. So, check your source. Cottonseed meal is also a very common ingredient in blended fertilizers.

Seaweed

Adds micronutrients and plant hormones! Derived from varieties of kelp harvested from the ocean then dried and ground into a powder form. Contains small amounts of nitrogen, phosphorus, and potassium. Many forms include kelp extracts in which compounds are extracted from the seaweed to concentrate the micronutrients and other helpful plant hormones. They are not high enough to correct deficiencies, but kelp provides plants and soils with a vitamin like effect.

Soybean Meal

Adds vital nitrogen to the soil. Usually one of the more expensive amendments, but very useful.

Sphagnum Peat Moss

Great to add to rough soils. Improves moisture retention.

Wood Ash

Another soil softener. Adds essential phosphate and potash. Can be a little high in pH (very alkaline) so go easy on it. Great to add to very acidic soils that are high in nitrogen.

ANIMAL BYPRODUCTS

Blood Meal

Use with caution or risk burning your plants. It’s dried and ground waste from slaughterhouses, primarily steer, and is a strong source of nitrogen.

Bone Meal

Slow release. Another common ingredient in fertilizer mixes, and due to its high amounts of phosphorus, should be used with care like blood meal.

Earthworm Castings

Clean, usually odorless, and can be used on all soil and plants. Castings, when concentrated, are rich in nitrogen but they will not burn plants. Castings vary but can contain magnesium, calcium, potassium, potash, micronutrients, and some trace elements. Grain fed castings tend to be the best and stay in the soil longer, while manure fed castings are a lower grade, but release their nutrients faster. More importantly, worm castings contain tons of beneficial organisms and microbes that help to restore soil life and begin recreating the soil web.

Feather Meal

Products of the poultry industry, the feathers are ground into a meal which contains levels of nitrogen which releases a little slower than other nitrogen sources.

Fish Meal

Ground and dried fish waste. A good source of nitrogen and some phosphorous too. Not to be confused with fish emulsion, which is a liquid form of the fish waste products and less stable.

Oyster Shell Lime

Sometimes grouped with dolomite lime, however it is derived from the shells of finely ground oyster shells rather than being rock-based like dolomite lime. Oyster Shell lime will raise pH, add calcium, and many micronutrients. The microbial life inside of your soil loves oyster shell lime!

Phosphorous Bat Guano

King of the phosphorus amendments! Fantastic crop sweetener! Not to be confused with nitrogen bat guanos, which are more of a manure product, phosphorous bat guanos are ground up fossilized remains of bat poop. The phosphorus releases slowly into the soil over time and contains beneficial microbes too.

Shrimp, Crab, and Sea Meals

Ground waste products from sea going animals that are not fish. Their waste is primarily their shells and exoskeletons which provide an excellent source of major nutrients as well as many micro-nutrients. They break down slowly, thus providing some staying power.

MANURE-BASED AMENDMENTS

Nitrogen Bat Guanos

Bat droppings that are fresher provide a great source of nitrogen. They contain some phosphorus, though not as high of levels as the fossilized bat guanos. Nitrogen bat guano is considered to be the best of the manures as they are nutrient rich, but very stable.

Poultry Manure

Quick and dirty fix of nitrogen – releases very fast. One of the poorer quality manures, but effective if used quickly and properly treated. It can burn your plants, so it must be amended into the soil and watered in before planting. Fish meal is preferable as it is more stable and does not decompose as quickly.

Sewage Sludge / Bio-Solids

Very cheap, very dirty: derived from human waste and whatever else got flushed, such as traces of household chemicals, bleaches, and paints. It can contain many harmful pathogens and heavy metals. Not nice.

Steer Manure

The farmer’s stinky favorite. Derived from steers and some equine. Very potent source of nitrogen and should be used truly to amend soils in preparation of planting. Best for large gardens and not small landscapes or containers. In bagged form, it is still very volatile and breaks down quickly.

COMPOST-BASED AMENDMENTS

Compost

Derived from decayed plant matter such as your left over vegetable scraps. Compost does include decaying animal matter as well, but for most gardeners it comes from vegetable and fruit scraps from your home.

Mulch

Plant and bark materials that are not fully decomposed. Aids moisture retention, decreases temperatures (protects from hot temperatures), weed reduction, and more.

ROCK & MINERAL-BASED AMENDMENTS

Dolomite Lime

Provides calcium, magnesium, and lowers pH quickly. It also helps with the breaking up of clay soils.

Greensand

A clay-type mineral supplement, greensand will provide potassium on a slow release schedule. It is very effective at improving soil structures though not so much as a fertilizer.

Hard Rock Phosphate

Derived from volcanic deposits and highly mineral in composition. The phosphate is not as available as in more traditional, soft rock phosphates, so it is not always the best amendment. However, with its mineral qualities, it can provide slow and steady mineral release into soils.

Humates

Derived from leonardite, humic and fulvic acids, humates help with the active part of soil’s humus. These goodies help with nutrient uptake by plants and assist under the soil too.

Perlite

Volcanic rock “rice crispies.” Perlite is inert and provides drainage and aeration in to compacted soils. Perlite rises to the top when watered, so it is not the best to add to in-ground plantings, though very important for containers and raised beds.

Rock Phosphate

Excellent, slow releasing form of phosphorus. Many sources have been mined deeply and contain levels of arsenic, so get it tested or check your manufacturers MSDS (Material Safety Data Sheet).

Vermiculite

Vermiculite is very light and can float in water. It is a great medium for starting seeds and amending soils as it contains some minerals and will help with aeration. Perlite provides better results for drainage and aeration, though.

Q) What Exactly Is “Compost”?

A) Compost is organic matter that has gone through a decomposition process. The organic material can be plant material or animal matter. Composting may seem complicated but it’s actually just a natural process that continuously occurs in nature without any assistance from mankind. It is the natural top soil in the woods. Both living plants and annual plants that die or drop plant matter are consumed by animals, large mammals, birds, rodents, worms, insects, and microscopic organisms.  The results of this natural cycle is compost, the remains are left on the forest floor to create rich, soft, earthy smelling soil.  Mmmmm!

Q) Where Does The Compost I Buy Come From?

A) Commercial composters work with waste haulers and organic waste generators to provide an alternative to landfills, leading to a reduction in the generator’s waste management costs. The material is diverted to a composting facility where it can be recycled into soil amendments and other value-added products.

Q) Can I Make Compost At Home?

A) Absolutely!  DIY Home composting helps to keep the organic material out of landfills and in turn makes a wonderful product for your garden. Composting at home is even greener and reduces the transportation. But don’t worry if you decide you don’t have the time or the room to do it yourself; most states have mandated waste management facilities to divert the greater portion of organic matter from the landfill to a composting facility. This has lead to an increase in the availability of mass-produced compost.  You can do your part by buying this lush beautiful soil amendment!

Q) What Makes Compost Good for Plants?

A) Compost is great for the environment and great for the garden.  Compost improves the soil by providing all of the essential nutrients plants need to thrive.  It releases the nutrients slowly over time giving the plants a slow, steady consistent source of the elements plants need.  Compost also improves soil porosity, structure, moisture capacity and air ratio.  Compost will improve the texture of any soil from sand to clay. Field testing has shown that compost improves plant vigor, overall health and the plant’s immune system.

Q) Where Can I Buy Compost?

A) Compost is available in most retail garden centers and is typically sold in 1 to 2 cubic foot bags.  Keep in mind the name “compost” is used generically and does not constitute its quality.  The mandates that forced the hands of garbage waste companies to compost organic matter has created some compost facilities that simply just do it because they have to. These companies are focused on the reduction of garbage and not quality compost. So look at the compost before you purchase it and ask yourself… Is it rich in color? Does it have a soft earthy smell? Is it free from garbage and large chunks of un-composted material?  If the answer is yes to all of these questions you are most likely working with a decent material. For more detailed information on the compost you purchased call the manufacture and ask for a soil analysis. If they are not happy to provide it find a company who is!  

Q) How do I Make My Own Quality Compost?

There are two basic kinds of compost piles: open bins and enclosed containers.

Typically composting at home is done in a pile, an open bin, or an enclosed container. A pile or open bin usually has little to no starting costs and it’s very easy to add your feeding materials.  Also, it will collect rain water easily.  Some considerations if you are planning a pile or open bin compost pile: it will attract wildlife, it can be an eye sore, it can get overly drenched during the rainy season and it can smell really bad! Also keep in mind you have turn the pile once in a while.

Container composting can either be done in an upright box or a rotating drum. These options are great at keeping out pests and are a bit easier on the eyes for you and your neighbors. Pay attention to the moisture content and be sure to turn your container as needed.

Compost Basics

Temperature: Letting the compost pile core heat to 160°F (71°C) will be beneficial for the decomposition of the material and will also kill off pathogenic organisms.  It will heat up naturally during the decomposition process.

Air and Water: Keeping your pile moist is simple.  However, keeping it oxygenated is more work. As the pile heats, the microbiology goes to work and, as the pile settles, the air flow is cut off and the pile becomes anaerobic. This is where we get our shovels out and turn the pile, flip our containers, or roll our barrels thus fluffing the pile and allowing the airflow to return.

Feeding your compost:

There are two basic categories of food source for a compost pile.  Although one or any combination of these materials will compost a good mix of them will compost more efficiently.  A good rule of thumb is about one part green and three parts brown; too much green creates smell and off-gasses some of your nutrients.  Too much brown will slow the process.

Typical green materials for compost are:

• Fresh (green) grass clippings
• Fresh manure (horse, chicken, rabbit, cow)
• Kitchen scraps (fruit, vegetables, coffee grounds, tea bags.  Avoid meats and fish.)
• Weeds
• Green leaves
• Leftover fruits from the garden

Typical brown materials for compost include:

• Brown, dry leaves
• Dried grass
• Cornstalks (shredded)
• Straw
• Sawdust

In conclusion, composting is great for the environment and fantastic for your garden. There are a lot of resources on composting but the best way to learn is to go for it and get your hands dirty!

So what’s the big deal about ‘organic’ and minerals for growing plants?

There is a conflict between definitions and scientific facts. The problem is that “organic” is not defined by ecologists or scientists – it is defined by bureaucrats, by government functionaries who often don’t have a clue what they are talking about from a purely scientific point of view and are often making decisions for special interest groups including organizations that put up a lot of money to twist the rules in their favor. ‘Organic’ has become big business.

The rules that define ‘organic’ vary from place to place. European rules that define ‘organic’ are significantly different from the rules in the United States. Canada has its own rules and many states in the US have different rules. Within the United States there is the NOP (National Organic Program) from the US department of Agriculture, there is OMRI (Organic Materials Review Institute), there is CCOF (California Certified Organic Farmers) to name a few… and there are many more regulatory groups. Their rules are not the same and their definitions are not scientific. They tend to be well meaning, non-scientific, closed minded groups that ‘know better’ and will apply their views to all who wish to use the term to make money.

On the other hand, when “organic” is looked at scientifically it’s really about protecting the environment and making more wholesome products – that’s what it should mean. But the bureaucrats and special interest groups have set different definitions. Fortunes are being made by companies selling weak and often ineffective products, and sometimes even harmful products, to a largely uneducated marketplace.

As a scientist I find value in both mineral and organic ingredients – and I am really looking at products from the point of view of what works better; what grows plants better, what gives customers higher quality and larger yields and what reduces the strain on the planet. That may or may not be ‘organic.’

Fundamental to the US ‘organic’ regulations is that purified ingredients cannot be used to make fertilizers; all ingredients need to be in their natural form … with some exceptions passed for special interests. This has led to some ‘organic’ ingredients having high levels of ‘heavy metals’ and sometimes pathogenic organisms such as E. coli and salmonella bacteria (this happens with mined ingredients and poorly composted materials that contain manures or other dead animal ingredients). If the poisons are removed, the product is no longer ‘organic.’ I consider this completely absurd.

One positive note is that fertilizer regulations in many places now require manufacturers to have their products tested for ‘heavy metals.’ This is a case where the rules provide the consumer some measure of protection from dangerous produce. I find that many state regulations for fertilizers are in fact very good rules offering the consumer assurance of product quality and consistency. Many of the state regulators I have worked with for years consider the ‘organic’ rules absurd. Nonetheless, rules are rules and regulators must apply the rules whether they like them or not, that’s their job. For more info see: www.aapfco.org.

I’m in my 32nd year in this business and I take the word “organic” very seriously. I’ve worked very hard in the field of modern plant growing technologies, always from a scientific point of view. If ‘organic’ was always based on good science and consistently resulted in better and healthier produce, faster growth rates and higher yields, as well as less impact on soil and water, I would be much happier about the definitions.

Can you describe enabling vs. triggering and the theory behind nutrient manipulation?

A good nutrient formula needs to stimulate all aspects of the plant’s growth and health – roots, stems, and leaves to start – the structural period of growth. And this means high nitrogen, appropriate phosphate, pretty high potassium, appropriate magnesium, calcium, and sulfate – and then of course the full spectrum of micronutrients. The plants go through their life cycle and they are triggered to change to the reproductive mode, typically by a change in day length – this is called ‘photoperiodism.’ An indoor gardener classically alters the light cycle from 18 to 12 hours of light per day. Within a week or so the plants start to express flowering. As we see the first evidence of flowering, we change the nutrient blend into something very different so the plants are better able to produce flowers. As the plants continue to grow we can further modify the nutrient blend, making it somewhat threatening to the plants. The plants respond by converting all their growing energy to produce flowers, to prepare for the next generation. Annual crops have a limited lifetime, of course – and they have the goal of growing up, becoming strong, and then generating seed for the next generation. It’s all about reproduction for the next generation. So you could say that plants are all about sex and they are all about their children. The essence of life is defined by a limited lifetime and preparation for the next generation.

When plants are growing in a perfect happy life, when they are young and in vegetative mode, they have no particular reason to reproduce. They’re secure and growing vigorously, becoming bigger and stronger. But when the trigger comes of day-length shortening, the plants are being told by nature that the winter is coming and the end of their life is at hand. And so, at this point the plants have to completely change priorities into reproductive growth. By switching the nutrients to something that enhances flower growth and reducing nitrogen significantly – the plants are now threatened by the nutrient regimen. They are not on a starvation diet, but a modified diet that stimulates and enables reproductive growth – kind of like a goose being fed for pate. There’s a different set of priorities going on from the grower’s point of view and the crop is responding. So now the job of the nutrient is to enable the plants to produce these wonderful flowers. So we’re really now about helping that crop to flower – tremendously, because flowers are the precursors to fruit and seed. We provide the elements needed for abundant flowering and we reduce the nitrogen that was needed for early structural growth while enhancing ingredients that enable flowering.

Remember, you cannot compel a plant to enter the reproductive phase with nutrients alone. Nutrients are enablers – not triggers. Day length change is a trigger. It’s telling the plant that winter is approaching, as the days get shorter. But when you apply a trigger you also need to apply an enabler so that the plant is able to make that transition. If we were growing in a deficient environment the plant would not be able to reproduce very well, so we provide what is needed for flower production and reduce the nitrogen that is fundamental to vegetative growth.

What is the difference between vitamins and nutrients?

Plant fertilizers are a very clearly defined group of minerals. The list is exact and they are all pure elements, or basic compounds made up of elements. Nitrogen, phosphorus and potassium are the primary nutrients. Calcium, magnesium and sulfate are secondary nutrients. Iron, manganese, zinc, copper, boron and molybdenum are the micro nutrients. Silicon has been added to the list of beneficial elements, to improve plant structure. Recent studies indicate that a little nickel and a little cobalt are also helpful (primarily for beneficial organisms that live in the root environment). We know from hydroponic studies that we can grow a healthy plant from seed to harvest on only those elements if they are provided in appropriate ratios and concentrations.

Vitamins and nutrient supplements are generally composed of complex organic molecules that are usually derived from plant and animal by-products, or synthesized from various compounds. In the case of animal-based ingredients, organic growers use blood meal, bone meal, feather meal, fish meals, and manures, literally the by-products of animals. These ingredients provide fundamental NPK as well as complex organic molecules which are broken down in the soil by microorganisms. Or plant tissue and microbial derivatives, such as compost, that also contain some NPK plus myriad organic molecules. It’s an extremely complex field.

A plant’s need for a vitamin or its production of a vitamin or other complex organic molecule are often derivatives of environmental phenomena. If a plant is threatened it will convert its chemistries internally, making whatever that plant is inclined to make. Perhaps a pheromone to attract beneficial insects, or another to drive harmful insects away. Notice the difference between essential compounds, which are the elemental minerals in fertilizers, and beneficial compounds, which include many of the ‘organics’ that people are showing interest in today. You can use some of these organic products to improve a crop’s quality, growth rate, yield, vigor and health but the plant can grow without them as a general rule. Take away any one of the mineral compounds required for plant growth and that plant cannot live – it cannot fulfill its genetic destiny.

Can plants absorb vitamins through their root system?

We didn’t used to think so. And for many years I would speak the old party line of “big organic molecules can’t fit through plant roots – just the mineral elements.”  I believe I was mistaken about that and I think that we are now learning that larger and more complex molecules can travel in and out of the plant whether through root tissue or foliar – there are various modes, usually with symbiotic microorganisms acting as doorkeepers to help the molecules into or out of the plant tissue.

Microbes living in the root zone help the plant absorb many of these natural compounds. Plants have a synergistic relationship with many of the organisms living in and on the roots. Ecto (living on the surface of roots) and Endo (living within the roots) Mychorrizae are good examples of beneficial fungi that live symbiotically with plants. By populating the root zone with beneficials, the bad organisms become challenged by the beneficials. Without the beneficials the roots have no protection. We have found with studies at the University of California that in many cases the complex organic compounds become most effective when the crop is under extreme stress: for example, high temperatures, inadequate moisture, or a disease are generally high stress situations. I’ve seen treated plants recover from moisture stress (not watered for a long time) next to untreated plants that never come back; this is an osmotic pressure imbalance model where plant tissue becomes dehydrated. A lot of crops are lost due to inadequate irrigation.

Another group of compounds that help plants absorb nutrients include the Humic and Fulvic acids. These organic acids often come from Leonardite, sort of an ancient or fossil form of compost. Many regulations do not recognize ‘Fulvic acid’ since there is not a standardized test to prove the presence or concentration of Fulvic acid. Technically speaking, Fulvic acid is a low molecular weight Humic acid. Fulvic acid works especially well with hydroponics. Humic acid is slower at enhancing nutrient absorption, and much less expensive. It is favored for soil cultivation though Fulvic is superior for both soil and hydroponics. Our product called Diamond Nectar is Fulvic acid derived from Leonardite, although we can’t make label claims due to regulations.

What other compounds are used by growers?

A group of compounds called Plant Growth Regulators (PGRs) have been developed to enhance certain characteristics in growing plants. For example, rooting stimulators are used to make cuttings grow roots and become copies or clones of the original donor, or mother plant. In this case the PGR is usually IBA (indole butyric acid) or NAA (naphthaleneacetic acid), or a combination. Plant tissue naturally contains IAA (indole acetic acid), a naturally occurring rooting hormone, and as a result cuttings will root without the added PGR if given adequate moisture and oxygen. The synthetic IBA is preferred because it is stable in a bottle and quite effective; IAA rapidly breaks down and does not store well.

There are many PGRs that are used by professional growers to enhance rooting, ripening, stem elongation or shortening, and numerous other unique characteristics. The entire family of PGR compounds is highly regulated, some are natural and safe, and some are synthetic and quite dangerous. Generally they are mutagens that cause radical changes in plant morphology. Labels will warn users to use skin and respiratory protection. They are generally regulated, not as fertilizers, but as pesticides. It is a bit strange that they all fall under the rules of pesticides even though they do not function as pesticides, another case of the rules being off track. The bottom line is that PGRs are often approved for ornamental plants but not for consumables. In some cases special licensing is required to purchase and use PGRs, as is the case with many pesticides and fungicides. This is heavy chemistry and not for amateurs. This is the antithesis of ‘organic’ cultivation even though most of the compounds fall under the scientific definition of ‘organic chemistry.’

I am aware of cases where manufacturers have added PGRs to fertilizers or supplements without proper registration or even a mention on the label. This is an area of moral responsibility and too many people are drawn by a desire for profit at the expense of the consumer’s safety. It is especially troubling for those who consume the produce grown with these powerful chemicals.

I will close by saying that, though I have issues with regulatory definitions and the way the rules are written and applied, the rules exist to protect the consumer and the environment. Growers should educate themselves and apply commonsense based on real knowledge when they grow produce for consumption. We all have a responsibility to use technology in a proper way, to grow better produce and to protect the environment. Just being an ‘organic’ grower is not enough. We are learning new things all the time and with the accumulation of knowledge and experience we can be productive and profitable while also being ethical.