Pollination

The flowers of the Dragon Fruit are big about 30cm across and beautiful. They also only bloom at night which is a main problem as the general pollinators like the bees and birds are missing. The flowers do sometimes open till around 8am in the morning but it will depend on the weather. Many of the varieties are not self-compatible; therefore, the flowers need to be cross pollinated with pollen from a different clone or species in order to set fruit.

On the safe side new plantings should use 2 or 3 different genetic types (not from the same clone). Cross pollination between the different genetic types in the plant will assure better fruit set and size. Moths and bats are good pollinators since flowers open at night when there is no bee activity.

Flower about to close with bees as pollinators

Hand pollination is one method to ensure that the flowers set fruit but this adds a considerable amount to the labor cost of growing these fruit. Hand pollination is carried out easily by physically removing anthers from one flower and touching them to the stigma of another or collecting the pollen and using a brush to pollinate multiple flowers. Pollen is most viable at the time of flower opening, but hand pollination was found to be successful well into the evening of the following day (Weiss et al., 1994).

Many of the varieties from Asia (predominantly H. undatus) are self-compatible, and some of these are autogamous and will set fruit without the involvement of a pollen vector. It has been previously reported (Weiss et al., 1994) that Selenicereus megalanthus, the yellow pitaya, is autogamous. The anthers and stigma are at the same height in these flowers and touch as the flower closes.

Anthers and Stigma are of same height

They also found that in their clones of Hylocereus species the anthers and stigma were separated by at least 2 cm. This may be the reason why their self-compatible Hylocereus undatus clone was not autogamous.

Anthers and Stigma of different height


Hand pollinating using a brush