Having just devoured Michael Pollan's The Omnivore's Dilemma, excellent reading for those interested in dissecting the complexities of green, we were delighted when Jill tipped us off to these movable greenhouses. The idea is brilliant and simple.
Because it is so intensively cultivated, the soil in a fixed greenhouse tends to become poisonous to the very plants you are trying to grow. This leaves the gardener in a bind: grow everything in pots, or attempt to periodically sterilize the soil.
But what if you could just move the greenhouse to a fresh plot? Inspired by examples in Europe, Eliot Coleman devised an entire greenhouse that sits on rails and can be pushed to and fro over two beds, allowing the gardener to cycle beds and keep the soil fertile. It's also well designed, with either glass or lighter weight polycarbonate available...
What can a gardener do with a movable greenhouse? The manufacturers suggest several uses:
• The house could be moved to cover strawberries or asparagus in early spring thus speeding up the first harvest by at least a month.
• It could advance a bed of spring bulbs or keep hardy annuals flowering through mid-December.
• You might move the greenhouse to protect globe artichokes over the winter or to cover fig trees in a climate where they would otherwise not survive.
Prices start at $9,500 for a standard 8' x 12' greenhouse and go up with size. The greenhouses are sold as a kit, so figure on extra for freight to your location, site preparation, assembly, and, if needed, permits.