Flexing your green thumb doesn’t have to mean getting down and dirty — at least if you opt for hydroponics, an alternative form of gardening that doesn’t use soil.
Sound like something from “The Jetsons?” Well, it kind of is. Back in 1990, NASA started testing a “salad machine” at its California-based Ames Research Center, with the starry-eyed hope that one day astronauts would be able to grow fresh, nutritious produce in space. No gravity, no huge open spaces, no soil and thankfully, no freeze-drying required.
While that plan hasn’t come into full bloom just yet, as recently as 2009, NASA was still talking about using the salad machines — “bioregenerative life-support systems” in rocket-scientist speak — to sustain human life for longer periods of time while exploring and potentially colonizing Mars.
According the book “Soilless Culture: Theory and Practice,” humans have been one-upping Mother Nature and growing plants in containers above ground for approximately 4,000 years, as wall paintings found in the ancient Egyptian temple of Deir el Bahari indicate. Yet soil-less horticulture didn’t really take root until the 20th century, as scientists made an effort to avoid the detrimental effects of soil-borne pests and pathogens.
Besides keeping gardeners’ hands a little cleaner, hydroponic farming keeps the earth greener, too. Among the benefits of hydroponics outlined in a report from the Uruguayan Hydroponics Society is the fact that the water used to sustain the systems is recycled and does not pollute the environment with harmful pesticides. Hydroponics use significantly less water than traditional agriculture, explains the Progressive Gardening Trade Association. For example, while it takes an average of 71 gallons of water to produce a single pound of traditionally harvested lettuce, only 3 gallons of water are required to do the same in a soil-free environment.
Scientists have been experimenting with an even more environmentally friendly form of hydroponics called aquaponics, a cross between aquaculture and hydroponics, in some very unlikely places. Since 1982, visitors to the “Living with the Land” attraction at Disney World’s Epcot theme park in Orlando have witnessed state-of-the art, whimsical horticulture — adorable pumpkins with mouse ears for Halloween, anyone? Mickey’s gardening staff provides a lot more than just amusement, however, hydroponics magazine Rosebud details. Disney’s use of aquaponics demonstrates that farmers can advantageously harness the symbiotic relationship — a fancy biological term for “win-win situation” — between the nutritional byproducts of fish in reservoir water and water-filtering hydroponic plants to yield more with less.
As if creating a self-sustaining, contained ecosystem weren’t enough, gardeners can really embrace the god-role by controlling the precise nutrients that are supplied to plants in their water, thereby maximizing the quality of produce harvested. You can’t do that in “FarmVille.” In a 1996 study from Purdue University and NASA published in Advances in Space Research, evidence was found that adding excess nutrients in plants’ hydroponic solution did have an effect on the levels of nutrients found in the final product — the produce itself.
A 2012 study from the International Society for Horticultural Science demonstrated that the size, length, stem diameter and fresh weight of lettuce plants grown without soil surpassed the results of a conventional soil-based farming system because as it turns out, plants, much like humans, are a reflection of what they eat.
Hydroponics also is space-efficient, and not just in the planets-and-galaxies sense of the word, as seen in Cornell University’s Controlled Environment Agriculture prototype. From 1999 to 2001, Cornell worked with 0.15 acres of growing space to produce a whopping 1,000 heads of butterhead lettuce per day. They were able to exceed that goal and harvest 1,245 heads of lettuce per day, or 70 heads of lettuce per square foot. That’s a lot of salad in the making.
Because hydroponics requires such little space, this type of gardening is ideal for urban-dwellers seeking to add more flora to their concrete jungle. Designers from Hyundai’s engineering and construction division recently collaborated with the South Korean design firm Gromo to dream up “Nano Garden,” a futuristic, vertical hydroponic unit that provides stacked shelves of gardening space for growing fresh veggies and herbs right in your kitchen.
Until the “Nano Garden” becomes a reality, gardeners tight on space can purchase a hydroponic kit from Windowfarms.com, which provides vertical indoor gardens for the year-round harvesting of edible greens from watercress and chives to flat-leaf parsley. The kits are complete with nutrient-enriched water that is pumped from a reservoir at the base of the system. Maintenance for a Windowfarm might be minimal, but the basic one-column Windowfarm and “starter pack” will set you back nearly $200.
For a more affordable, DIY option, the University of Florida’s Small Farms & Alternative Enterprises Program provides step-by-step instructions on how to make a 4-foot by 8-foot floating hydroponic garden for around $50. With easy-to-find materials like wood, a Styrofoam insulation sheet and water-soluble fertilizer, you, too, can be a scientist, conducting horticultural experiments on your little controlled ecosystem. (White lab coat not mandatory.)
So you might not get to fulfill your childhood dreams of becoming an astronaut after all, but at least you can eat — and garden — like one.