May 7, 2016
Dot Zanotti Ingels
Hydroponically grown vegetables are starting to make more appearances on restaurant menus and in markets but, if you are like me, you really do not understand why that is a good thing and worth the extra cost. Basically, hydroponic gardening is the growing of plants without the use of a traditional dirt medium but using an aerated, nutrient-rich water solution.
Growing plants hydroponically has been utilized for thousands of years. The Floating Gardens of Xochimilco the Aztecs created in Mexico City 1,000 years ago are still in use. Historical records show that hydroponics was utilized in the Hanging Gardens of Babylon. In the 1930s, Pan American Airlines grew hydroponic vegetables to feed passengers on Wake Island, a rocky, soilless, remote refueling atoll in the Pacific Ocean. NASA has done extensive research in hydroponics for use in the space program and on Mars. Plants that cannot traditionally grow in a particular climate can be made possible using a controlled environment like hydroponics.
NASA and many university studies have shown benefits of hydroponic growing that include:
• Savings of at least 90 percent of the water (for indoor hydroponics) and 60 percent of the fertilizer utilized in soil culture growth. The water savings differ between outdoor and indoor hydroponics because of evaporation and other variables that limit control of the growing conditions outdoors.
• Efficient and contained fertilizer usage means no runoff into waterways.
• More food can be harvested in less space and with more annual crop cycles. Giving a plant exactly what it needs when it needs it keeps that plant as healthy as genetically possible.
• Works well in areas with limited water, poor soil or limited space.
• There are no problems with soil-borne diseases and pests.
• It is sustainable.
Hydroponically grown plants are anchored by a growing medium other than soil. These are inert substances that do not provide any nutrition to the plants and are just there to provide support for the plant while the roots grow down into the nutrient solution. These growing mediums include expanded clay aggregate, rock wool, perlite, vermiculite, coconut fiber, gravel or sand. Formulating hydroponic solutions is based on plant science and a lot of chemistry. High quality commercial products are readily available and reasonably priced.
There are several methods of hydroponic gardening. They vary in their complexity and the quantity of supplies needed. As you can imagine, a large hydroponic operation is usually done in a controlled greenhouse environment with pumps, temperature controls and so much more.
But you can do it at home. It can be as simple or as complex as your time and your budget are willing to provide. Bernard A. Kratky, a professor of agriculture at the University of Hawaii, has designed systems that do not use mechanical aeration or circulation. This allows off-the-grid home garden hydroponic growing that gives the same excellent results as more expensive, high-tech methods. Opaque buckets or plastic totes are fitted with lids that hold net pots that hold the medium that will support the plants and allow roots to grow down into the nutrient solution. You can find YouTube videos to help you make one yourself or you can find them at a hydroponic garden provider.
To find out so much more about the world of hydroponic gardening, please join UC Marin Master Gardener, consultant (and hydroponic gardener on his floating home) Stan Barbarich at one of three seminars he is offering on “Hydroponic Outdoor Gardening” from 2 to 3 p.m. May 9 at the San Rafael Public Library at 1100 E St., from 10 a.m. to 12:30 p.m. May 14 at the Mill Valley Library at 375 Throckmorton Ave. or from 10 a.m. to noon May 21 at the Novato Library at 1720 Novato Blvd.