[SIZE=-2]Roots emerging from their container.[/SIZE]The Organic Method
The secret to organic hydroponics is the creation of a hydroponic grow container that allows for organic nutrients to be applied directly to the upper primary growing medium rather than into the lower secondary water receiving root system. (See Diagram 1. for a cutaway drawing of a grow containers.)
In order to create a simple organic hydroponic system, you may use a standard hydroponic grow container, or a coir fiber container. The standard grow container is first filled with lava rock half way up from the bottom of the container. The upper remainder of the container houses a simple mixture of 1/3 coarse grade horticulture perlite, 1/3 large-sized horticulture vermiculite, and 1/3 potting soil. You should place a thin layer of hydroponic medium, such as loose coir fiber, or loose rockwool on top of the lava rock. This will act as a "medium divider" to prevent any of the soil mixture from dropping down into the lava rock. This layering of mediums best promotes the upper capillary action of the water and prevents any organic particles from flowing downward into the bottom of the grow bed.
If a standard plastic hydroponic grow container is used, a plastic screen lining fitted on the inside circumference of the entire container, from the bottom up the sides to the top, will further prevent most small particles of the soil mixture from getting into the water if a standard plastic hydroponic container is used. Using a hydroponic container with small holes is helpful also.
[SIZE=-2]Fresh cuttings preparing to root.[/SIZE]Coir fiber containers are excellent for this also, the construction of the coir fiber container will prevent any loss of soil. A large coir fiber container is filled about half way up from the bottom with lava rock, or any suitable hydroponic material. A small dividing layer of loose or strand coir fiber is placed on top of the lower medium, and then a soil or my suggested soil mixture is placed in the upper section of the container.
The container is then placed in the grow bed with the water level just slightly below the "soil" line. The submerged lava rock, or other hydroponic medium along with the secondary root system, will encourage the capillary flow of water upward into the soil, thus keeping the soil mixture or medium always moistened. The separate upper and lower sections may also be watered independently. The lower section may be continually watered throughout the day on a hydroponic schedule, different from perhaps once a day watering, which would only be required for the upper "soil" section. (See Diagram 2 for container placement.)
The upper soil mixture or medium is where the nutrients may now be placed. As the water reservoir periodically moistens the lower medium, moisture and air are drawn into the entire root structure of the plant, at regular intervals. Thus the plant is supplied with more of the vital oxygen and CO2 that enables them to metabolize the nutrients much faster.
[SIZE=-2]An organic garden of hydro delights![/SIZE]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.
[SIZE=-2]Pumping up a plant.[/SIZE]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.
