Undercover Device: The Cloche

Image Gallery Here the finished cloche is shown in place, with its heavy plastic cover stretched tight over the PVC hoops and then tied with rope.

Increase your garden's productivity with low-cost, manageable, season-extending structures.

by Johanna Linch

One harvest, two harvests, three harvests, four ...Wouldn't it be wonderful to be able to grow fresh fruits, flowers, and vegetables for your table all year round? Unfortunately, for most of us the growing season is limited to just a few months out of the year. Cold, wind, and excessive precipitation dictate when and for how long plants will grow. Until soil and air reach a certain level of warmth, for example, flowers and vegetables cannot germinate. And, at the other end of the scale, they go dormant—or die altogether—when temperatures drop below a certain point. Then too, heavy seasonal rains can drown young seedlings, wash them out of the soil, or beat them into the ground, while strong winds occasionally batter and break tender leaves and stems. All this means that, without special help of some kind, most plants can only be cultivated between the dates of the last spring frost and the first frost in autumn or during the benign days between the end and new beginning of the rainy, superhot, or storm seasons. In some areas this results in a growing season of two months or less—too little time for many of the most desirable crops to mature.

There are ways to bypass the weather, however, by giving plants the environment they need to flourish out of season. Structures such as the greenhouse, the cold frame, and the hotbed can all provide the necessary microclimate for crops to be started earlier in spring and allowed to mature deeper into autumn. Still another way to control the environment is through the use of cloches.

BELLING THE CROP

Cloches—a term that means "bells" in French—have been used extensively in the garden since the 1800's. To advance their crops for market, nineteenth-century French gardeners placed bell-shaped glass jars over individual seedlings to protect them from frost and to give them warm, undisturbed surroundings in which to grow. These early cloches had no holes for ventilation, so they had to be tilted and propped open with a stick or stone when excessive heat or moisture built up inside. Because each individual plant had its own cover, maintaining adequate ventilation for a large crop was tedious and time-consuming; furthermore, storage of the glass bells from one season to the next required a lot of space and sometimes resulted in costly breakage. Therefore, over the years gardeners have sought ways to improve on this basic design; and although empty peanut butter and canning jars—modern versions of yesteryear's elegant glass domes—are still used today, new devices made with metal and plastic have greatly improved the situation.