“Flowers begin to form when there is a branching of the pepper plant. There is dicotamous flowering, meaning that one flower forms, then two, then four, then eight, and so on. The number of flowers produced is very large compared to those which actually set fruit, and a larger percentage of the early flowers set fruit than the later flowers. The key factor affecting fruit set is night temperature, which ideally should be between 65 and 80 degrees F. Fruit will not set when the temperature is above 86 degrees at night because of excessive transpiration, which causes blossom drop. Other causes of blossom drop are excessive nitrogen, high winds, and lack of pollination. If daytime temperatures exceed 95 degrees, pollen will abort and the fruit set will be reduced.
In addition to the methods described above, pepper gardeners have discovered other ways to produce more pods. One of the most common practices is the removal of flowers and early fruit. Dr. William Clapham, a plant physiologist at the University of Maine, recommends pinching off flowers for several weeks to increase fruit dry weight. He suggests that the pepper plants devote their energy to vegetative growth rather than fruit production, resulting in larger plants that produce more market-sized fruits. In another experiment, plants with all flowers removed as late as mid-July still had good yields.
During the hottest days of July and August, many pepper plants experience water loss by transpiration, no matter how wet the ground is. The results are wilting, flower drop, and sometimes even fruit drop. Antitranspirants, oil or wax emusions sprayed on leaves to reduce water loss, are available. They do reduce water loss, but they do not increase yield or pod size. The simplest method of fighting transpiration water loss is to increase the humidity around the plants by wetting thick layers of mulch such as grass clippings.”
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