Hydroponic Greenhouse Gardening

Initially hostile to the whole concept, the author describes why he changed his view of hydroponics and established a hydroponic greenhouse.


| September/October 1974



029 hydroponic greenhouse - 11 rows of plants

Plants in the author's highly successful hydroponic greenhouse.


PHOTO: MOTHER EARTH NEWS STAFF

In "Build an Ecosystem: The Earth-Sheltered Solar Greenhouse" I described a homemade ecosystem, an underground hydroponic greenhouse and aquaculture tank which I recently built on my small New Mexico homestead. In that article I discussed the construction procedure and philosophical rationale of the project. Now I'd like to expand on some of the details: in this installment, specifically, the subject of hydroponic gardening.

The American Heritage Dictionary of the English Language defines "hydroponics" as follows:

hy-dro-pon-ics (hi' dre-pon'iks) n. Plural in form, used with a singular verb. The cultivation of plants in water containing dissolved inorganic nutrients, rather than in soil ....  

Most plants grown hydroponically are raised in greenhouses under carefully controlled conditions. Gravel is usually used as a medium for root support, and a balanced mixture of all the necessary nutrients is periodically fed to the crops in a liquid form. This method is called "sub-irrigation culture." In large commercial greenhouses it's been refined to such a degree that—once the seedlings have been planted—almost all the work is done by automation. Delicate sensors in the gravel "decide" when the plants need more solution and turn on pumps which meter out the correct dosage.

The biggest advantage of the hydroponic method is that crop yields are increased many times over those of conventional agriculture. For example, the yield per acre of tomatoes grown in soil is from five to ten tons. With hydroponics, the harvest is from 60 to 300 tons! For cucumbers, the equivalent figures are 7,000 pounds compared with 28,000 pounds ... for lettuce, 9,000 pounds and 21,000 pounds.

For years I'd heard about hydroponic gardening, but had never given the subject more room in my thoughts than a quickly contemptuous dismissal. After all, hydroponics is the quintessential form of chemical agriculture. To a dyed-in-the-wool organic gardener like me, the thought of feeding my vegetables with a pure chemical solution was blasphemy. Then one day about two years ago, I was browsing in a bookstore and came upon a thin newsprint pamphlet with the title Hydroponics!. My first reaction was an almost irrational disgust: "What kind of propaganda are the big chemical companies putting out now?" But the work had the aura of a counterculture publication: large format, cheap paper, and on the cover a reproduction of Buckminster Fuller's Dymaxion map of the world. I picked up the booklet, gingerly leafed through it, and then bought it on the spot.





Crowd at Seven Springs MOTHER EARTH NEWS FAIR

MOTHER EARTH NEWS FAIR

Sept. 15-17, 2017
Seven Springs, PA.

With more than 150 workshops, there is no shortage of informative demonstrations and lectures to educate and entertain you over the weekend.

LEARN MORE