Clever gardeners who love their hobby can stretch their vegetable gardening season.
Northern gardeners will begin starting seeds indoors as early as January--particularly herb seeds, which take along time to germinate.
Another way of stretching the season is to create outdoor enclosures that allow plants to be growing in the garden long before they would normally survive...and after the first frost of autumn has wilted most gardens. For years, gardeners have used cold frames for this purpose. This is a deep, bottomless wooden box, slanted toward the sun, covered with glass. Old wooden storm windows are often used to cover cold frames. They are propped open for ventilation, as the days grow warmer. Plants started in the house are moved into the cold frame while the last frosts of the year continue.
One of the most versatile season stretchers is called the caterpillar cloche (shown above and at right). It can be used in the backyard garden or adapted to planters on the deck or patio. It allows you to plant outside three weeks earlier than usual, and harvest three weeks longer in the fall. It is designed for beds or planter boxes three to four feet wide. The caterpillar cloche consists of a length of clear plastic film 4 mils thick or thicker and a series of supports made out of 3/4-inch stiff, black plastic tubing of the type used for water lines. This is cut with a hacksaw into sections 6 feet by 8 inches long. The general idea is to bend the tubing to form a series of hoops three feet apart. These can be anchored into the ground by pounding "pilot" holes about six inches deep with a stake and then pushing the tubing into the hole. You can start three feet from each end of the bed.
Cut the plastic film to be two feet longer than the bed and about eight feet wide. The plastic sheet is stretched over the arched supports and held down on either edge with soil or stones. The ends are gathered and tied to stakes pounded into the ground just beyond the ends of the bed.
You can adjust for high or low plants by making the hoops longer or shorter than our specifications.
A variation on the idea can be used on patios and decks or even in the garden. Instead of pounding holes into the ground, the ends of the hoops are pushed into holes drilled into a frame of 2- by-4s. Drill the holes at an angle that will accept the tubing. The ends of the plastic film can be tied to a cleat on the frame.
In early spring, start plants outside in the cloche and either leave them to grow where they are or transplant them to other areas of the garden. As the days grow warmer, open up the plastic film according to weather conditions.
After the last frost of spring remove it completely and bring it back in the fall to protect crops from an early frost.
Another option is to put up the cloche after the garden season has ended in fall and the soil has been turned over. Left up all winter, the soil under the cloche will be steaming and warm while there is still snow on the ground. You can plant lettuce, spinach, onions and peas under it. You'll be harvesting salads before most people have begun their gardening season.
Just before the first frost, find a pepper plant that has several small peppers forming. Dig it up, pot it, and bring it indoors to a sunny window to allow the peppers to mature.
Take cuttings from basil and other annual herbs. Bring them indoors and pot them in soilless mix after dippinq the ends in growth hormone. To prevent drying, cover the pot with plastic. A plastic soda bottle with the bottom cut off works well as a miniature greenhouse. Once they are established you can remove the greenhouse and have a windowsill herb garden all winter.
For small planter boxes or garden beds, look into the plastic domes used to cover basement windows. Fastened back to back, they make a handy small greenhouse.