Solar Greenhouse

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Getting the most from your

In winter, every inch of growing space is precious.

by Nancy Bubel

Remember how much you longed for your first bicycle— or car? That's how much I wanted a solar greenhouse! Many a winter I raised seedlings under fluorescent lights, always wishing the abundant sunlight of our south-facing land could reach my starts.

Well, dreaming, planning, and saving finally led to building. And now there is a modest solar greenhouse attached to our small Pennsylvania home. But, as always happens when I get something I've longed for, the realized dream brought with it a challenge: learning to use my greenhouse well. So, over the past few years, I've studied, experimented, and observed carefully, and—even though I still consider myself a beginning solar gardener—I've learned a lot I'd like to share.

A Room of Many Uses

Solar greenhouses can be much more than a place to start spring seedlings. Mine provides such delights as crisp cucumbers in December, green chard in January, and succulent Chinese cabbage in February. It also

• protects tender herbs and geraniums over winter,
• dries mint and such in summer,
• cures harvested onions and garlic,
• yields a fall harvest of potted peppers, tomatoes, eggplants, cucumbers, and such, and
• easily roots cuttings of grapes, geraniums, and herbs (I use the loose, moist soil of my large growing bed for this).

Whatever design you choose for your greenhouse, I heartily recommend that it include a large growing bed. The soil will serve as an excellent, moisture-retaining plant home and will provide mass for absorbing and holding the sun's warmth.

When we built our greenhouse, we left the growing bed's foundation open for drainage. We shoveled 3" of gravel into the bed, and we topped that with a layer of 4"-thick "books" peeled from bales of spoiled hay. Next came 4" of decomposing wood chips, 4" of compost, and 8" of loose garden soil mixed with several large bagfuls of vermiculite and commercial potting soil.

Each year we add another 2" to 3" layer of compost and about three quarts of wood ashes to the bed. We dig in clean, fine-textured kitchen scraps such as coffee and tea grounds . . . and toss in a few earthworms from time to time to help digest the scraps, aerate the bed, and add rich castings.