Organic Hydroponics
By David Roberts
During a day and age when our environment is becoming increasingly toxic including the air we breathe, the water we drink, and the food we eat; more and more of us are turning to the natural alternatives that are available. We are starting to consider how future generations may be affected by the pollution being produced in the name of capital gain, be it corporate or personal. These considerations are responsible for the dramatic increase in the consumption of organic products. Whether the product is shampoo or herbs, these products all fetch a substantially higher dollar value. Contrary to popular opinion, hydroponic gardens are not limited to chemical fertilizers. It is possible to use organic fertilizer in a hydroponic garden. Organic substances are those that are still in their natural state not having been through chemical re-composition, and these can include substances produced by animals and plants.
Hydroponic crops are excluded from certification under the B.C. Certified Organics Program; however, this does not mean that we cannot reap the benefits of an organic harvest. Long has the debate been argued between those in favor of organic gardens and those who are indifferent or otherwise. What advantages could there be in an organic garden? As we know there are 16 plant nutrients that are essential for survival. We are aware of hormones that regulate plant growth, and we utilize B vitamins. There is, however, a lot more for humanity to learn.
Do we want our plants to just ‘survive’ or is our objective to obtain a maximum yield? We are currently learning about the relationship between plant growth and enzymes. According to some, all plant metabolic processes are enzyme driven. Plants use energy to move water and nutrient through cells up to the leaves where through the process of photosynthesis these elements are converted to sugars and starches which are in turn sent back down to the root zone for possible storage. Plants must produce the enzymes necessary to take up these nutrients, minerals, and vitamins. This process also requires energy (sugars and starches); now consider how much extra energy your plants could use for fruit or flower production (cellular mitosis) if we supplied a good portion of these enzymes. Enzymes also play other important roles in plant growth, for example, we all know the dreaded destruction that root disease can wreak upon a garden. Why aren’t all the plants that live outside dying of Pythium infection? Simply put, Mother Nature takes care to balance this relationship by creating naturally occurring enzymes and beneficial microbes that keep the root zone free of this crippling sickness. We are very fortunate to be able to obtain sophisticated enzyme formulations which contain numerous enzymes. Dead and decaying root matter is the substrate upon which Pythium will grow, that is why whenever we have root disease we see that our roots are soft to the touch and usually falling apart. Enzymes can dissolve this decaying root matter and convert it to sugars and starches, thus pulling the carpet right out from underneath the feet of root disease. This is one of the components of dynamic plant growth that occurs in nature that can bring indoors to our hydroponic gardens.
We have been aware for the last 150 years that naturally occurring humic and fulvic acids increase nutrient uptake by basically forming a bridge between the nutrient and the root zone, humic acid is also beneficial to break down organic nutrient compositions. The importance of humic acids, often overlooked in aquatic systems has become apparent as research shows us that humic acid can comprise 95% of the total dissolved organic matter in an aquatic system. Humic acids are also of utmost importance in microbial processes, as well as interacting with over 50 elements from the periodic table and containing stable populations of free radicals. There is a granular humic acid formulation available which could be mixed into a hydroponic medium. Nature has a way of taking care of itself and when we consider that the DNA of every living or extinct species of organism on earth, including plants, animals, or microbes, eventually becomes a highly refined component of a truly high grade fulvic acid such as General Hydroponics Diamond Nectar we can clearly see that there must be beneficial results in plant growth and the breakdown of the organic matter which we are relying on to feed our plants. It is very important to know that true high grade fulvic acid will greatly increase the uptake of nitrogen which can result in drastic internodal stretching. Many gardeners find that utilizing a very light foliar spray of fulvic acid every morning for the last two weeks of flower enhances favorable characteristics.
It is possible to propagate a cutting organically as well. There are a number of organic rooting hormones available on the market. Traditionally, organic rooting hormones such as willow tree extract or liquid seaweed take much longer to initiate the rooting process than a synthetic rooting hormone. However, there have been reports of some plants rooting just as quickly. When it comes to the choice of a rooting medium one can choose whichever yields the most success. Organic-based starter plugs manufactured from composted bark are available, and some contain beneficial bacteria such as Trichoderma and are available under a variety of trade names.
Often overlooked is the importance of microbial processes that occur in nature. These beneficial organisms take decades to develop in the subterranean levels of the earth and now we have the chance to bring them indoors and add them to our gardens. Mycorrhizal products are a rarely used product in this industry, but are actually very useful in expanding the root surface which consequently increases nutrient uptake. Most claim to be 100% natural, are inexpensive products to use, and generally take only one application to establish a healthy and flourishing population of beneficial microbes.
It is very easy to garden organically utilizing a drain to waste system with peat and perlite as the medium base. More often than not peat is referred to as ‘dirt’ implying that it is soil, when actually peat is a hydroponic medium due to the fact that it is inert. A sample mix which has been consistently used successfully is one bail of Pro Mix, 110 liter bail of perlite, a 20 litre bag of worm castings, one cup of rare earth, and one container of Myke Flower. To increase drainage of the medium even further, one could place about three inches of hydroton on the bottom of each pot. With this mix a gardener could expect a 20%-30% run off, for example if 100 gallons of nutrient were fed to the pots 20-30 gallons would run out from the holes in the bottom of the pots, therefore it is useful to have the pots placed in a 4×8 table equipped with a drain. This type of system is in theory borderline between true soil and hydroponic gardening, in effect utilizing the best of both worlds. In considering the components of our nutrient solution to use with this combination of mediums the choices are almost endless. It is important to note that in the above recipe we have not listed any organic components which are stronger or more active in nature such as bat guano or fish and crab meal, we are relying on our nutrient solution to provide us with the staple components necessary for optimum performance. Be very careful not to get carried away loading up a medium with organic foods, once you mix something in you cannot take it out, you can however, adjust your nutrient solution. One gardener who had decided to ‘go organic’ after having excellent results with his initial experiments became so brave that he loaded his peat mix full with a variety of organic products such as fish bone meal, bat guano, and so on. When he put his babies into the medium they crisped up and died due to severe root tip burn. The gardener ended up having to bake his pots under HID lighting for 2 weeks before he could put any plants into the medium. The pots would steam and become extremely hot due to the actively and rapidly breaking down organic matter.
In short the organic matter was too highly concentrated. Just because something is organic doesn’t always mean that it is not strong or readily available to the plant.
It must be said that there is much we do not know about the benefits of many components present in nature, and these unknown elements: Vitamins, minerals, enzymes, acids, microbes, and hormones are precisely what we stand to benefit from. Just because we do not know how it works does not mean that it doesn’t give us positive results.
There are so many factors involved in obtaining a maximum yield that is impossible to say that gardening organically will increase yield or quality. The popular notion that organically grown food is healthier for consumption is partly based in the non-use of pesticides. Pesticide use, when not strictly regulated and controlled, is highly hazardous to the environment, wildlife, and people. Pesticide use will also dramatically reduce yield in a garden, therefore it is definitely an advantage not only in production but in the future of our planet to make use of biological and natural pest control.
Options to consider in this extremely important area are predatory mites, insects, and nematodes. In order to obtain pleasing results using biological controls one must be educated on the specific environments that each control requires. For example spider mites like to be hot and dry, where predator mites like it a little cooler and more humid. In order to successfully use predator mites we must create an environment that will slow down the reproduction of the spider mite and speed up the reproduction of the predator mite. We can do this by lowering our temperature to 80 degrees Fahrenheit and raising our humidity to 60%. In these conditions we will have a positive experience with biological controls. British Columbia is one of the leading users of biological controls in the world, with many greenhouses actually introducing the pest first and then biological predator, thus creating a balanced environment. Other options include using natural products in a pest management program such as earth juice essential spray and neem oil. These products would require frequent use, approximately every three days. When we consider that as many as 16 different types of pesticide residue have been found on a single head of lettuce it becomes truly apparent that we must hold ourselves to stricter standards.
The other basis for the idea that organically grown food is healthier is the non-use of chemical fertilizers. In a strictly scientific sense, organic nutrients are broken down to chemicals before they are actually taken up by the plant. So, technically speaking as far as nutrient absorption is concerned, the difference only lies in the fact that organic nutrients contain more than the 16 elements deemed ‘essential ‘ for plant survival. The plant cannot technically tell the difference between nutrient derived from organic sources or from fertilizer salts.
The basic principles of gardening Bioponically are generally the same as far as the considerations of choosing a medium, irrigation cycles and so on. A major point of consideration is that organic nutrient formulations tend to be thicker, even chunkier, than a liquid chemical fertilizer. This characteristic makes a drip application very difficult, and Aeroponics almost impossible. The use of very fine micron filters is necessary in these systems if the nutrient solution is to be organic and drippers or misters should be checked daily. Flood and drain or drain to waste systems, however, work just fine with an organic nutrient solution. Drain to waste systems in fact are gaining tremendous popularity especially in Australia, many gardeners are utilizing perlite as the sole medium with several irrigation cycles throughout the day. If the drain to waste system is utilizing spaghetti line to irrigate the medium it would again be necessary to check that the lines are flowing freely on a daily basis.
It is possible to formulate our own organic nutrient solutions by making a tea with organic substances such as bat guano, worm castings, and so on; these solutions would have to be thoroughly filtered. There are pre-formulated organic teas available such as pure blend, pure blend pro, earth juice, and sea mix. Actually, there are far too many to name, and the truth being that some may work better than others. No matter which ones you choose, the following are some products that would benefit your nutrient solution. One such product is humic acid. Catalyst altered water is another. It will allow each single water molecule to carry an increased amount of nutrient up the root zone. Both of these products would increase nutrient uptake which is important in organic gardens because the parts per million strength of the nutrient solutions is much lower due to the fact that the nutrients are not present in the form of salts. Another very interesting organic product is catalyst altered water. If one studies the components of this product, one will see that the formulation contains much needed calcium and magnesium as well as fossilized organic material. Is it possible that we may be able to benefit from the same elements present in the age of the ancient giants that roamed the earth? Why did dinosaurs and all the plants present at that time grow so very large? There may be a great advantage in utilizing the fossil matter of that period.
It is still very important to monitor pH, and there is organic pH up and down formulations available. Some organic products have very extreme pH measurements. It is of course still very important to change the reservoir on a regular basis, or run a drain to waste system.
Some awesome examples of growing organic gardens are aquaculture which utilizes fish waste to feed the plants and plants to clean the fish water, the primary cost is fish food and the ideal fish is tilapia. Another example is a combination chicken and rose greenhouse, a 30’x120′ greenhouse atop a chicken coop produces $7,000 in chickens and $36,000 in roses every year. Forty tons of straw and twenty-five tons of chicken waste are reduced to six tons of hydroponic nutrient over the year.
Another fantastic example would be the extremely environmentally sound “green building” where plants are used to clean human waste from water. A remote community of 46 mobile homes became the proud user of the first natural sewage treatment system of this kind in B.C. when their failed septic system began polluting the ground water creating a health hazard. Not only is the process odour free it also produces bedding plants for their own use as well as wetland and tropical plants which are sold to the local nurseries.
Regardless of the reason for considering gardening organically, it is well worth it. Fertilizer salts have only been around for a very short period of time compared to the history of agricultural cultivation. Will millions of years of evolution change the natural relationship that plants have with all that surrounds us? Sometimes we have to look back to go forward.