Dragon fruit
is produced from a climbing cactus plant known as pitaya or pitahaya; the fruit
is also called pitaya. In Hawaiian it is known as paniniokapunahou or papipi
pua. A famous hedge of pitaya, with its triangular fleshy stems, is growing at
Punahou School on O`ahu. From July to October the hedge blooms with a wall of
white flowers hundreds of yards long. This type is considered an ornamental
that occasionally bears a few small, red fruits. Like many species of pitaya,
it is self-sterile, that is, a plant not capable of reproducing with its
own pollen. Recent breeding programs in Taiwan and Vietnam have resulted in the
development of many self-fertile and productive pitaya varieties.
Since the pitaya plant blooms only at night, when many insect pollinators are not active, successful pollination is sometimes difficult to achieve for adequate fruit bearing. Moths and bats are the likely pollinators for pitaya plants. If moth and bat populations are low, pollination will be limited; some backyard enthusiasts have resorted to hand pollination.
To help with pollination, gardeners can turn outside lights on in order to attract moths in the evening during the bloom period. Heavy rainfall during this time, would cause a lack of moth flights, and therefore, poor fruit production. For good fruit production, it is important to choose the right variety.
Dragon fruit plants prefer a warm, moist climate with rich organic soil. It is not suitable for areas with extreme high temperatures and intense sunlight. The plant will tolerate short exposures to freezing temperature and will recover rapidly. It requires 25-50 inches of rainfall annually. Excessive rain can cause flower drop and the fruit to rot. Commercial plantings of pitaya can be found in Vietnam, Taiwan, Malaysia and Israel.
Above photos by Forest and Kim Starr
University of California Cooperative Extension