An organic garden of hydro delights!
Since the water reservoir is not used to distribute the nutrients as is done with the "traditional" chemical method, there will be no need to worry about the nutrient PPM of the water. The reservoir will be used for the periodic watering of the lower secondary medium and root structure only. Using this organic method makes hydroponic growing as easy as soil growing by eliminating the need to keep a fine-tuned and precise chemically-balanced water reservoir.
With the organic hydroponics method, all of the organic nutrients are applied directly to the upper "soil" medium, much as they would be applied to any soil. If the organic nutrients used are in a liquid form, they are simply mixed to a proper concentration, the same as would be for soil application, and poured on the top of the medium. The secret is to not apply too many liquid nutrients at once.
Different mediums will have the capacity to hold water more than others. To find out the capacity of your upper medium, simply pour 1 cup of water in the upper section of the hydroponic container filled with medium. If 1/4 cup of water runs out the bottom, you may conclude that the moisture-holding ability of your particular amount of medium is slightly less than 3/4 cup. Next pour ½ cup of water into another container of your medium. If no water runs into the lava rock or out the bottom, you will then know that your medium will best retain 1/4 to ½ cup of nutrients per feeding.
You do not want to feed your plants with more nutrient-filled water than the medium will hold or you will drip nutrients into the lower secondary section and the bottom of your grow bed where they will then be returned to your reservoir. If during some feeding you notice a bit of nutrient water dripping from your grow container, into the grow bed, it is a simple job to just soak it up with a rag. If you notice any nutrients seeping down from the bottom of the upper grow medium into the lava rock, change the lava rock and use less liquid, or no liquid nutrient as a delivery system.
Pumping up a plant.
I recommend that you grow your plants in my standard medium formula: 1/3 perlite, 1/3 vermiculite and 1/3 of organic potting soil, or any loose 100% organic soil mixture, in the upper section. This combination of ingredients holds the nutrients and facilitates the upward capillary action of the water delivered from the reservoir. Using an organic soil based upper primary medium will create microbial action.
If you wish, you may mix organic nutrients, such as worm castings, directly into the soil mixture. The organic nutrients may also be mixed into a half cup of water and poured evenly across the top of the upper primary medium. Or you may choose to spread organic nutrients on the top of the upper medium, followed by a fine misting of water directly on the top of the medium. With any of these application methods, the organic nutrients will enter the soil to be utilized by the plant.
The upper "soil" or "soil alternative" where the nutrients are delivered should be treated just like any standard soil container. A light spraying once or twice a day to moisten the upper medium will assist the capillary action of the water from the lower hydroponic roots and lava rock.
If a small bit of nutrients drain downward into the reservoir, it is all right. The larger volume of water in the reservoir can absorb a small amount of organic nutrients without causing a problem. Standard chemical reservoirs need to have their water reservoir changed every week to two weeks and the same is true with this process. The reservoir water is changed every 1 to 2 weeks, depending on your ability to keep it clean.
Diagram by Sijay
Place lava rock in the bottom half of the hydroponic grow container, place a ½ inch medium divider of some hydroponic material, such as coir fiber, to prevent the soil from falling into the rockwool. Then place the medium of choice in the upper portion of the plant container. Place the container in the grow bed, so that only the lava rock will be watered. Using the Ebb and Flow method, when watering make sure the bottom of the upper medium will not be touched by the circulating water. If the circulating water touches the bottom of the upper medium, it may leach nutrients into the water in the reservoir. As the water circulates around the lower half of lava rock, a portion of water will capillary up through the medium divider and into the upper medium. (See Diagram 3. for a cut away drawing of organic water system.)
As the plants grow in the containers, they will develop two separate root systems. The upper root system will not use a hydroponic medium as the lower section does. I recommend that you use my standard suggested "soil" formula, or any organic soil, for the upper medium layer. You may use any organic nutrients, delivered either as a tea, spread on top, or mixed into the strata of the medium, with any of these hydroponic mediums.
The upper primary root system will develop a thick web-like matrix and structure of fine roots, similar to roots in standard soil. The upper medium will not be submerged in the water as the roots in the lower half of the container. The upper root web will allow for an enormous uptake of nutrients and create faster and more abundant growth. Plus the similar hydroponic nature of the upper medium "soil" mixture will allow additional oxygen to be exchanged within the medium.
In the lower half of the container filled with the lava rock, pumice, gravel, or sand, perlite, the secondary system of roots will develop. They will appear as the standard stringy, rope like structures common to hydroponic growing. There will be some fine hair-like roots, but not as abundant as those roots growing in the upper soil medium. These secondary roots, as with any hydroponic system, will take up water and, between watering cycles, be constantly exposed to more oxygen, which promotes faster metabolism and plant growth.
The water cycle may need a half hour, or less, to moisten the entire upper primary medium. If your upper medium takes longer to become completely moistened, then simply circulate the water at a slightly longer interval until the medium is properly moistened, or simply water the upper section separately, with a fine mist spray. The upper soil or medium only needs to be moist not soaked.
The development of a dual root structure will create a fast metabolizing growth system for your plants, that utilizes the essential processes and benefits of both soil and hydroponic gardening.
Diagram by Sijay
The organic nutrients placed in the upper soil portion of the container create roots that are allowed to develop in microbial activity, while the lower roots intake water as they are specially designed to do. This development of a dual root system creates a hydroponics process that is more similar to the growing processes in Nature than any other hydroponics process thus far.
The evolution to total organic hydroponics brings additional benefits to the entire world of hydroponics. This unique process eliminates the major problem of disposing of the chemically-laden water after the water is used in the standard hydroponics system. It eliminates the reliance on the hard-to-dispose of rockwool, or other nutrient filled waste material. And it permits the use of totally organic materials - from the mediums to the nutrients – throughout the seed to harvest stages.
Hydroponics gardening is rapidly growing in popularity, as well as changing in technique. Evolving from the Ebb and Flow method, the Nutrient Film/Flow Technique and Aeroponics. It was not too long ago that Semi-Organic Hydroponics arrived on the scene. And now, with Totally Organic Hydroponics, you can grow 100% hydroponics organically!
I hope you will enjoy this wonderful new way of gardening. While growing your plants to a certain stage of maturity for personal use, follow the simple instructions in Totally Organic Hydroponics, and you will be well on your way to becoming an expert organic hydroponic gardener.
- This process is detailed in Paul Wright's new book, Totally Organic Hydroponics. www.organiponics.com