Supermarkets raising their home-grown veggies in hydroponic greenhouses is science that smacks of science fiction.
Picture it. Steamy rooftop gardens under glass structures where a bounty of fresh produce is grown in a sterile, controlled environment. Seedlings sprout from nutrient-enriched water beds. Growth is fast. The yield is big and pesticide-free.
This is the stuff that NASA scientists play with. But it is being made possible by entrepreneurs who have formed companies with feel-good names like Gotham Greens, Bright Farms and Sky Vegetables.
They are touting the benefits of hydroponic farming and eyeing supermarkets, which have a built-in market for anything locally grown, as a logical host. SN Editor Michael Garry says that growing rooftop produce  would be the ultimate in local sourcing for supermarkets.
Besides providing an additional revenue stream, supermarkets can promote their good stewards of the earth image by investing in this technology.
Advocates say supermarkets can reduce their carbon footprint with environmentally sustainable systems that operate with solar panels and recycled rainwater.
Dickson Despommier, professor of public health at Columbia University, wrote in a recent op-ed piece in The New York Times: “The farms would greatly reduce fossil-fuel use and greenhouse-gas emissions, since they would eliminate the need for heavy farm machinery and trucks that deliver food from farm to fork.”
He envisions an urban Hanging Gardens of Babylon where the city landscape is transformed by vertical gardens. Buildings will be made translucent to capture sunlight and better accommodate the gardens that appear to hang in space while they clean the air of carbon dioxide and give off oxygen.
If this isn't enough to convince food retailers where they should invest their cap-ex dollars, there is the creation of green jobs, educational opportunities and possible government subsidies.
What is not to like about this model? It screams — “Feed me, Seymour!” (Remember the ever-growing, carnivorous Venus fly-trap plant in “Little Shop of Horrors.”)
Back to reality, there are the cost, infrastructure questions and the debate about hydroponic vs. organic. Organic purists question whether the nutritional value and taste are the same as earth-grown veggies from the farm stand down the street.
The cost appears feasible when considering that the cost of a new 45,000-square-foot supermarket can be over $6.5 million and a remodel for the same size store about $2.8 million. Gotham Greens' rooftop facility is $1.4 million.
However, experiments in this innovative concept have taken place in the past and haven't hit mainstream. In the late '80s, Japan's Daiei supermarket chain reportedly installed a factory farm to grow produce for its store in the Tokyo suburb of Fanabashi. Whole Foods today is tinkering with an herbal version of the concept at its Millburn, N.J., store.
So far this all remains science fiction and unproven commercially here. Given global environmental concerns, however, it is a model that cries “feed me!”