IDEAS FROM ABROAD, SOME OLD, SOME NEW
This report is based on information found in
HYDROPONICS IN ISRAEL
Hydroponics in Israel: Most of Israel is arid and has little water available for crop production. This has given rise to the use of hydroponics on a large scale, more so percentage-wise than for any other country. Also the proximity of the European market for cut flowers such as carnation, roses and chrysanthemums has given a sharp rise in hydroponic usage. Lately a large expanding market for foliage has come into existence.
NFT in the ordinary sense isn't used. A method called Ein-Gedi is used instead. In this method the plant's roots are immersed in a deep flowing solution. A fully developed mist is allowed to develop in the space between the light cap and the surface of the solution. This space is completely filled with mist. In some cases the entire trough is full of mist with no liquid at all flowing through the trough. The roots have ready access to oxygen and food.
Plant growth is effectively controlled by varying the ratios of the mist with the nutrient solution. Aside from Ein-Gedi, sand and tuff cultures are the leading methods used in Israel. Tuff culture is foremost in some parts of the country. Tuff is volcanic ash used for the planting medium. Tuff holds water and air, making a perfect medium. Since drip irrigation is one of the foremost feed and watering mechanisms used in Israel, tuff culture allows for its continuous use without injury to root systems.
Tuff contains permanent as well as variable ion charges; so care must be taken to have the correct pH and nutritional balance. This includes the balance between tuff and the solution. Growers believe in daily fertilization. Therefor leaching must be done now and then with large doses of water in order to prevent salt accumulation.
European buyers don't like the tuff medium; so some growers are now using expanded clay, an artificial gravel which is manufactured from clay and a lot of heat.
Sand culture is used along the Mediterranean Sea where climatic conditions are not as severe as in the interior. This is "dune" sand - it has relatively large particles and a very low ability to hold ions or water. Sand culture of this kind is responsible for Israel's creation of drip irrigation, because the sand has to be moist at all times. This is especially true when using salt water.
The growers of Israel are among the very few who have learned how to use salt water with plants. The secret is to use frequent applications in a trickle irrigation pattern. Both water and nutrients are fed at predetermined rates, depending upon the chemistry of the sand and the needs of the crop. This is all automated; therefor larger crops can be expected.
Cabutz is made from manure which has been composted and then watered to make a slurry. This mixture is run over a screen which separates the liquid from the solids. The liquid becomes fertilizer; the solids become a medium for plants. Some think that cabutz may be the answer for economy as well as for quality.
With ideas like these, it's no wonder the growers of Israel demand attention. Their climate and soil places them at the front line of hydroponic development.
WE HAVE THREE BOOKS THAT MAY BE OF INTEREST TO YOU.