Keep in mind that it is the freezing of the water that gives off the heat to protect the crop. Therefore, liquid water must be present during the freezing period to protect the plants. Bulb enlargement Snap bean Pod enlargement Pepper Planting to fruit set and enlargement Tomato Early flowering, fruit set and enlargement. The use of plastic mulch involves either clear or black plastic. Clear plastic is used to warm the soil, primarily for early crop production, but it does not control weeds.
Black plastic provides weed control and is used with several warm-season crops.
An advantage of plastic mulches is that they provide an even moisture supply. Yields of peppers, eggplant and summer squash are higher most years, and harvest can be up to 7 days earlier then unmulched plantings. Clear plastic mulch commonly is used to produce early sweet corn. Sweet corn can be planted in hills, single rows or double rows. Herbicides are applied prior to laying the plastic.