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Q & A With Lawrence Brooke Founder General Hydroponics

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Q & A With Lawrence Brooke Founder General Hydroponics

Q & A With Lawrence Brooke Founder General HydroponicsWe managed to track down Lawrence Brooke, one of the founding fathers of the modern hydroponics and indoor gardening movement, and asked him for his take on organics, nutrient triggers and enablers, vitamins and a whole lot more! Here’s what he had to say …






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 favour. ‘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 micro nutrients. 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.

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  1. I agree that the vitalistic movement has been around for a long time, and isn’t showing any signs of giving up. There are many “organic” materials that are capable of causing damage to both fora and fauna, and lab made oxidane can be used interchangably with it’s “natural” form in most instances.

    I don’t like the term “organic” unless talking about the presence of carbon, or as a general concept. I’m much more concerned with how many resources are consumed-ruined in a given process than if something is in it’s unpurified form.

    Not all chemicals are bad, not all organic materials are good, and the reverse is also true.

  2. Oh Good, I’m inspired. I often wondered about the one two part etc. I usually use “Formulex” to kick off with, for clones and young plants in particular, but have been advised on numerous occasions to change to 2 part asap once the plants are beginning to flourish, as the 2 part solutions will provide all the necessary nutrients. and 1 part solutions lack “certain” elements. Formulex however is often cited as a complete, and fully balanced solution best for soils, but in particular, ideal for young plants and clones. Well, that may well be so, I expect one could grow right through the flower phase, with the right EC and maybe some additives along the line, to compensate, or enhance. But perhaps the yield might not be as good, although that is often difficult to pin down as there are so many factors that can affect yields in the first place from species, through strain, environment, type of system etc etc. But I can understand Callie’s point made that dismisses the myth that 1 part is only used by novices.Technology does make things easier, well, sometimes, unless you need to follow translated instructions on how to set up the latest gizmo on the market. But definitely seasoned growers as well as novices will use single part, and many in between, if they understand the facts of the contents that is, and wish to manage their time more efficiently, and at the same time probably avoid some of the pitfalls when solutions are mixed. I liken it to the auto box on my car, in the UK a lot of cars use a manual gearbox, and yes, it can give the driver more control, but for me, give me an auto box anytime, point and squirt. Brilliant in slow moving traffic. Modern technology allows a very efficient transmission these days with computer chips lurking in every crevice, that was not around 10 years ago.

    Up until now I have generally used a 2 part Canna Aqua flores, pretty good, but it adds up in costs of course, with 2 bottles, A and B each time. There are a lot of companies touting them of course, each claiming the best results, or at least presenting the product in such a way that suggests they are better performers. I think many growers just find something that works for them, and sticks to that, it saves the need to start comparisons all over again. “If it works don’t fix it” mentality, but then again, why not embrace change, and improvement if it is available. That to me seems the more logical approach.
    So yes,I think I will go ahead and try out some of the Vitalink 1 part, I am curious, and probably a bit lazy! and I’ll see how things work out.

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