The Growth Cycle of the Pistachio

Pistachios grow in heavy grape-like clusters, and like almonds, are surrounded by a fleshy hull. Pistachios ripen in late summer or early autumn, their hulls becoming rosy and their inner shells splitting naturally along their sutures.

Pistachio orchards can successfully bear nuts for centuries in what are known as “alternate-bearing” cycles, i.e., their crop yield is heavy one year and light the next. Unlike almonds, pistachios produce male and female flowers on separate trees. Thus, in order for pollination to take place, both male and female trees must be present, or alternately, branches from male trees must be grafted onto their female counterparts. It requires wind—not bees—to carry pollen from male to female flowers.

At harvest time, pistachios are knocked onto a catching frame, never allowing them to touch the ground. From there the nuts are loaded onto containers and rushed to the processing plant. Pistachio nuts must be hulled and dried immediately to preserve their delicate quality and to prevent their shells from staining.