The National Organic Standards Board plans to decide this week whether hydroponically grown foods, a water-based model of cultivation, can be sold under the label "certified organic."

But some organic farmers and advocates are saying no — the organic label should be rooted in soil. The decision at stake for the $40 billion-a-year industry will have impacts that reach from small farms to global corporations.

Farmer Eliot Coleman is among those who oppose giving hydroponic produce the organic label. He recently joined other farmers at a rally in Thetford, Vt. They were holding signs saying "soil is the soul of organic."

"As far as we're concerned," Coleman says, "if it's not grown in soil with all the wonderful features that soil puts into the plants, there's no way you can call it organic."

Coleman's peers call him an "elder of the organic movement." The calluses on his hands are stained with soil. Coleman thinks that the central principle in growing organic produce is that the farmer feeds the soil, not the plant.

Part of the legal qualification of organic farming — and, in Coleman's opinion, the label consumers have come to trust — is about the healthfulness and stewardship of the land.

But Mark Mordasky, who owns Whipple Hollow Hydroponic Farm, says a sustainable model is important to him, too.

"We're in a greenhouse," Mordasky says. "We're not doing anything with the land, good or bad. We're not irresponsibly using land. We're simply choosing not to use land at all. Does that make us not organic?"

His greenhouse looks like it could have been designed by the late Steve Jobs — sleek and clean with rows upon rows of identical tomato plants stabilized in organic coconut fibers.

These plants are fed liquid fertilizers, which could be made from organic materials. But Vermont's organic certifiers bar Mordasky from labeling his produce as organic.

Mordasky thinks that, on a planet with fewer places to grow food and more mouths to feed, different growth methods should be accepted under the organic label.

"If we had all of our nutrients organic, all of our pesticides and herbicides — whatever we're doing to control disease was organic, and the medium itself that the roots are growing in is also organic, all the inputs are organic. The outcome, it seems to me, would be organic," he argues.

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