Reduce / Reuse / Recycle

May 24, 2006


Hydroponic Method Using Organic Fertilizer Developed

Keywords: Environmental Technology Reduce / Reuse / Recycle University / Research institute 

The National Institute of Vegetable and Tea Science in Tsu City, Mie Prefecture announced on January 18, 2006 that it has developed a hydroponic cultivation method using 100 percent organic fertilizer, instead of conventional chemical fertilizers. The institute claims that cultivation techniques using unprocessed organic matter, such as fish stock and oil meal, have not yet been reported elsewhere in the world.

Hydroponics is a method of cultivating plants using a culture solution containing the necessary nutrients instead of soil. This technology was inspired by the technique of "shubo" (seed mash) for Japanese sake, which uses microorganisms to produce ethanol from starch. By creating an ecosystem for microorganisms that can decompose or mineralize the organic nitrogen in organic matter into nitric acid, the total volume of fertilizer can be converted into organic fertilizer.

For this technique to be mobilized, a small amount of soil is first added to a tank full of water -- about five grams of soil to each liter of water -- for inoculation purposes. With a continuous supply of oxygen through an air pump and as little as 1 gram of organic matter per liter every day, microorganisms start to grow. In two weeks, this solution can be used for hydroponics. Organic fertilizer can then be added directly in response to crop growth.

The results of experimental cultivation using this technique have shown that the growth of tomatoes and butter lettuce with fish stock and corn steep liquor (leftovers from starch production) is comparable to that with chemical fertilizers. This method has drawn attention as a technology contributing to a recycling-based society as it enables both crop cultivation and degradation of organic waste, such as beer yeast and tofu lees, a byproduct from tofu production. The institute plans to expand this method by demonstrating the feasibility of solid organic fertilizer from corn meal, fishmeal and other sources in the future.

Posted: 2006/05/24 03:00:00 PM
Japanese version