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Framing a plan for fresh greens


"And a little bit of mesclun mix" was the last thing I heard before closing the door and heading for the supermarket.

Not much to ask. A little arugula, some oak-leaf lettuce, radicchio, sorrel and frisee give a salad a complex peppery/bitter/sour tang. And, it's all premixed in a bin at the supermarket. Nothing could be easier.

A few minutes later, as I stood in front of that bin, reality set in. It was late winter, and the lovely mixes of the late autumn had yielded to a sad sight - a box full of dried-up, wilted greens shipped from fields thousands of miles away.

Last winter, my wife and I wished that the greens of summer could last all year. Then we came across a book by Eliot Coleman, an organic gardener, who said they could. He wrote that with a cold frame, a kind of mini greenhouse, gardeners can keep fresh greens on the table all year long.

He uses one in midcoast Maine. If he can succeed there, we figured we could do it here in Baltimore and welcome fresh and tasty salads to our table all winter long.

On Sept. 16, when we set to work, the weather was terrific. With lumber purchased from Home Depot and three windows salvaged from a neighbor, we built a box 3 feet deep and 8 feet long.

We painted the boards and windows to discourage rot and termites, then nailed the whole thing together in half an hour with little fuss. The windows tended to rub against each other when we opened and closed them, but at least there was a tight seal.

The longest and most intense sunlight in our yard shines on the front lawn, so out came the sod. We fitted the frame in place, positioning it so the front faced south to catch the winter sun as it tracks low across the sky. We enriched the soil with compost, peat moss and some composted horse manure - a gift from sympathetic neighbors.

We selected the seeds of plants that we knew were hardy in cool temperatures and that we liked to eat. So, turnips, radishes, carrots, endive, mache, spinach and a spicy mesclun mix went into the soil - tall stuff going in the back and the shorter in the front.

We wondered how neighbors would react to the big box. Appearing as it did so close to the attacks on Sept. 11, one neighbor asked if it was the entrance to a bomb shelter.

Within days, the plants were springing up in the cold frame, thanks to the mild fall temperatures. But there was danger in fair weather. On one especially nice day, the inside of the cold frame reached 126.4 degrees Fahrenheit. It had become a lettuce sauna.

My heart sank looking at the result. Some of the smaller stemmed greens looked wilted and I expected that we would have to replant from the beginning. And yet, the radishes and turnips looked great, so I watered, left the windows open and hoped for the best. Within a day or two, everything bounced back. We were lucky, the price of mesclun is eternal vigilance.

On a few very cold nights, the temperature dropped drastically and we put a tarp over the frame around sunset and pulled it off in the morning. This gave us great results. On most nights, the frame was 10 degrees to 12 degrees warmer than the outside air.

Mulch, dirt and even snow packed around the frame made terrific insulation and sunlight penetrated several inches of snow to warm the inside.

What won't penetrate is rain, so we had to remember to water, learning to only water the soil - not the leaves - and only when the frame has warmed up in the middle of the day. Water on the leaves can freeze and damage the crop.

Not everything we did worked. The oak-leaf lettuce didn't come up at all. The windowpanes became loose and the paint peeled. Next year, we will look into a silicon caulk for the windows and some sort of wood preservative that will be food-safe.

But as a whole, the experiment worked. The greens that have come out of the frame have been crisp, fresh and flavorful, meeting our high demands each month. We put a heavy crimp in the supply with a Thanksgiving harvest, but between reseeding and additional growth our supply bounced back.

Now, however, we find ourselves in a Catch-22. Extending gardening into the winter means we spend cold winter days outside babying our charges, cleaning out molded leaves, checking for aphids, weeding (yes, grass does grow in the winter) and constantly monitoring the changing weather of the mid-Atlantic. There is no rest for the gardener.

But this winter, as we ponder what we have raised and the joy of eating fresh winter greens with a juicy pot roast supper, we are making plans for more and bigger frames next fall.

Fit for a frame

Not everything will grow in a cold frame. Tomatoes, peppers, eggplant and cucumbers are a few that need warm - even hot - weather to thrive. Here are some greens and vegetables that will do well in a cold frame:



oak-leaf lettuce


Swiss chard







For more information, check out Four-Season Harvest by Eliot Coleman, (Chelsea Green Publishing, 1999, $24.95).

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