My favorite use for medium-weight row covers is to guard members of the cucurbit family (melons, squashes, gourds and cucumbers) against damage by striped and spotted cucumber beetles. I cover transplants immediately after they go in the ground, before the beetles spot them. Hoops (five-foot pieces of nine-gauge wire) are spaced every four to six feet down the row to hold the fabric clear of the plants’ leaves.
The covers stay in place until the mature plants bloom. Then I remove them to allow pollination by bees and other insects. By the time plants are mature, the beetle population has diminished. Even if insects attack them now, the plants will produce a crop before they succumb. Some cucurbit varieties form fruit without pollination by insects, so covers can be left in place until harvest.
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