Selenicereus undatus

Dragon fruit (Selenicereus undatus)
Dragon fruit of the species historically called Hylocereus undatus.
Scientific name	Selenicereus undatus
Former horticultural name	Hylocereus undatus (Haw.) Britton & Rose
Genus	Selenicereus
Family	Cactaceae
Order	Caryophyllales
Growth form	Climbing or sprawling cactus with aerial roots
Native range	Conservative Central American range; native limits are difficult to separate from cultivation
Climate and site	Tropical to warm subtropical; protect from hard frost
Propagation	Stem cuttings; seed for breeding
Years to fruit	N/A — highly method-dependent; cuttings may fruit in 6–9 months, seed-grown plants much later
Pollination	Variable; some forms need compatible pollen or hand pollination
Fruit and harvest	Red or pink-skinned fruit, commonly white-fleshed; local season varies

Dragon fruit (Selenicereus undatus) is a climbing cactus in the genus Selenicereus, family Cactaceae, and order Caryophyllales. Horticultural literature often uses the former combination Hylocereus undatus; that name is retained here as a synonym or historical placement while the modern accepted name is used as the canonical title.^[1][2]

Description

The plant has fast-growing, three-sided succulent stems with wavy wings and aerial roots. It may climb trees, rocks, or a trellis. Large fragrant white flowers open at night. The berry is usually red- or pink-skinned with white flesh and many small black seeds, although dragon-fruit cultivation includes related species and hybrids with other colors.[1][2]

Distribution and habitat

Native limits are difficult to separate from cultivation and escape. Useful Tropical Plants gives a conservative Central American treatment, including Honduras, El Salvador, Guatemala, and north to central Mexico, while UF/IFAS uses a broader tropical-American context for pitaya horticulture. The species occurs in thickets, hedges, on rocks or walls, and as an epiphytic or terrestrial cactus, sometimes to about 2,000 m.[1][2]

Cultivation

Provide strong support, rapid drainage, and warm bright conditions. The plant is cactus-like but has a fairly high water requirement during active growth; drought tolerance does not justify constant saturation or poor drainage. Young plants may benefit from about 30% shade during the first few months or in intense sun, while mature plants generally flower and fruit best with strong light and airflow.[1][2]

Soil and water

Use porous, very well-drained mineral or sandy loam with organic matter. Useful Tropical Plants reports an acidic preference around pH 5.3–6.7, with a broader tolerance; UF/IFAS emphasizes well-drained soil and organic amendments. Irrigate periodically during flowering and fruit development, but keep the crown and stem bases out of stagnant wetness because excess moisture promotes root and stem disease.[1][2]

Sun and humidity

Full or nearly full sun supports production, with temporary light shade for young plants or extreme heat. Prune and train the canopy so stems and fruit dry after rain. Humid air can support growth, but enclosed wet foliage without ventilation increases disease pressure.[2]

Seasonal changes

A dry interval in winter and early spring can support bloom induction. Once flowering begins in late spring and summer, drought can reduce production, so maintain moisture through flowering and harvest. Cool or short-day conditions slow flowering and growth; protect stems from prolonged cold and reduce irrigation during cool dormant periods without allowing container media to remain wet.[2]

Propagation

Stem cuttings are the normal garden and commercial method and preserve the parent type. UF/IFAS describes curing 12–38 cm segments for about 7–8 days in a dry, shady place before planting into well-drained media. Seed is useful for breeding but is variable. Years to fruit is N/A as a single species-wide value: UF/IFAS reports that seed-grown plants may take up to about seven years, while many stem cuttings can fruit in approximately 6–9 months after planting under suitable conditions.[2]

Flowering, fruiting, and harvest

Flowers are large, white, hermaphroditic, and nocturnal. Some cultivars are self-incompatible; two or three genetically different plants or hand pollination can improve fruit set and size. In the Florida extension account, fruit ripening for the older Hylocereus treatment is generally June–November, but local temperature, photoperiod, cultivar, and rainfall change the calendar. Harvest fully colored mature fruit with clippers, cutting the peduncle close to the fruit.[2]

Fruit and uses

Ripe fruit is eaten fresh or chilled. The mild, lightly sweet flesh is used in drinks, smoothies, salads, preserves, frozen desserts, and pastries. Young unopened flowers are cooked as a vegetable in some regional cuisines. White flesh is characteristic of the commonly treated species but should not be used alone to identify a cultivar or a related dragon-fruit species.[1][2]

Photos

Whole and cut dragon fruit showing white flesh and black seeds; the file uses the former Hylocereus name.

References

• ↑ [1] Useful Tropical Plants: Hylocereus undatus — synonym/legacy name, habitat, cultivation, fruit, and uses.

• ↑ [2] UF/IFAS: Pitaya (Dragon Fruit) — horticultural name usage, soil, water, shade, pollination, propagation, years to fruit, and harvest.

Image credits

• Fruit of Hylocereus undatus.jpg — Gaurav Dhwaj Khadka, CC BY 4.0; whole fruit held in a hand.
• Hylocereus undatus-fruit20180201 118(07,24,36).jpg — Bff, CC BY-SA 4.0; whole and cut fruit showing white flesh and seeds.