My broccoli plants were driving me crazy. One by one, the sturdy seedlings would keel over and die. Out of every
dozen, only five or six made it to harvest. The culprit, I decided, was root maggot, the larva of a fly that lays its eggs on broccoli leaves. A gardener friend suggested covering my broccoli bed with a fabric called Reemay. I was skeptical, but I gave it a try the following spring, stretching the fabric over wire hoops to form a tunnel. I kept a garden diary in those days, and the entry for June 20 reads, “Reemay prevented root maggot from attacking broccoli. 100 percent crop!” It was no fluke. Every broccoli I’ve planted under a row-cover tunnel since that spring has survived to succulent adulthood, often maturing faster than normal. And I have become not only a convert of the Reemay tunnel but also a missionary.

Use wire to hold the tunnel up and rocks to hold it down

A brand name that has become generic, Reemay is just one of a number of row covers on the market. Some, like Reemay, are made from spun-bonded polyester; others are made from spun-bonded polypropylene. Their fibers are not woven but pressed together. Nevertheless, they are strong and so light that a square yard weighs a mere
½ ounce. These fabrics are ideal for covering seeds or plants because they are porous to air and water and 85 percent transparent. Sunlight penetrates a row cover to warm the air and soil, creating a benign microclimate for germination and growth. All floating row covers will take the edge off a frost, but to play it safe, especially with heat-loving transplants, I watch the forecast and add extra cover when the prediction is ominous.

Keep the tunnel intact until the weather warms

Despite the tunnel, I still have to cope with weeds, which grow with tropical exuberance under the cover, and with underground pests, but I no longer worry about flying and leaping insects because they can’t penetrate a row cover. Rabbits and woodchucks could chew through, but they are too dim to recognize the opportunity. In a row-cover tunnel, my cold-crop transplants get a significant boost, and my warm-weather transplants can be set out two weeks earlier than usual.

 Except when I pull back the fabric to weed or water, my transplants remain under cover as they grow. There is no fixed time when I remove the fabric and take down the hoops. When the broccoli, cabbage, and cauliflower begin to push against the sides and tops of the tunnel, they are ready to make it on their own. With spinach, I cast off one side, weed and thin, then cover again until the remaining plants mature. I lift the cover from tomatoes, peppers, eggplants, and other warm-weather crops in late spring; frost no longer threatens, and now the plants are strapping adolescents.

 When the fabric is no longer needed, I check it over, mend holes and tears with duct tape, clean off any mud, roll it up, stuff it in a bag, and store it out of the way of mice. I’m sure I could construct row-cover tunnels again in fall to extend the other end of the season, but my plants are well played out by then—and, frankly, so am I.