After thorough cleaning of the seeds from the pulp of the fruit, the seeds may be stored when dried. Ideally, the fruit must be unblemished and overripe. Seeds grow well in a compost or potting soil mix - even as a potted indoor plant. Pitaya cacti usually germinate between 11 and 14 days after shallow planting. As they are cacti, overwatering is a concern for home growers. As their growth continues, these climbing plants will find something to climb on, which can involve putting aerial roots down from the branches in addition to the basal roots. Once the plant reaches a mature 10 lbs weight, one may see the plant flower. Pitaya cacti flower overnight, usually wilting by the morning. They rely on nocturnal creatures such as bats or moths for fertilization by other pitaya. Self-fertilization will not produce fruit. This limits the capability of home growers to produce the fruit. However, the plants can flower between three and six times in a year depending especially on growing conditions. Like other cacti, if a healthy piece of the stem is broken off, it may take root in soil and become its own plant. This is a much shorter route to reproduction. The plants handles up to 104oF and very short periods of frost, but do not survive long exposure to freezing temperatures. The cacti thrive most in USDA zones 10-11, but may survive outdoors in zone 9a or 9b.
Hylocereus has adapted to live in dry tropical climates with a moderate amount of rain. The dragon fruit sets on the cactus-like trees 30–50 days after flowering and can sometimes have 5-6 cycles of harvests per year. There are some farms in Vietnam that produce 30 tons of fruit per hectare every year.
Pests and diseases
Overwatering or excessive rainfall can cause the flowers to drop and fruit to rot. Birds can be a nuisance. The bacterium Xanthomonas campestris causes the stems to rot. Dothiorella fungi can cause brown spots on the fruit, but this is not common.
Stenocereus fruit (sour pitayas) are of more local importance, being commonly eaten in the arid regions of the Americas. They are more sour and refreshing, with juicier flesh and a stronger taste, and are relished by hikers. The common Sour Pitaya or pitaya agria (S. gummosus) in the Sonoran Desert has been an important food source for Native American peoples. The Seri people of northwestern Mexico still harvest the highly appreciated fruit, and call the plant ziix is ccapxl – "thing whose fruit is sour". The fruit of related species, such as S. queretaroensis and Dagger Cactus (S. griseus), are also locally important food. Somewhat confusingly, the Organ Pipe Cactus (S. thurberi) fruit (called ool by the Seris) is the pitahaya dulce ("sweet pitahaya") of its native lands, as dragon fruit are not grown there in numbers. It still has a more tart aroma than Hylocereus fruit, described as somewhat reminiscent of watermelon; it has some uses in folk medicine.
Fruits of some other columnar cacti (mainly Cereeae) are also called "pitayas" – for example those of the Peruvian Apple Cactus (Cereus repandus).
See Also: florist Paris, Vietnam flower, India flower