Dragon fruit berries are edible and have bright red skins and white pulp. A delicious tropical fruit, they also have a high nutritional value. Dragon fruit is a climbing plant with aerial roots and often climbs on tree trunks, abandoned walls, or boulders. It requires plenty of light but is easy to care for and can be planted in a yard.
I. Appearance and Characteristics
Selenicereus undatus, the white-fleshed pitaya, is a species of the genus Selenicereus (formerly Hylocereus) in the family Cactaceae and is the most cultivated species in the genus. It is used both as an ornamental vine and as a fruit crop – the pitaya or dragon fruit.
Like all true cacti, the genus originates in the Americas,S. undatus originates from Mexico to Honduras; it may be a hybrid. It is most frequently attributed to the island of Martinique in the West Indies
Dragonfruit stems are scandent (climbing habit), creeping, sprawling or clambering, and branch profusely. There can be four to seven of them, between 5 and 10 m (16 and 33 ft)or longer, with joints from 30 to 120 cm (12 to 47 in) or longer, and 10 to 12 cm (3.9 to 4.7 in) thick; with generally three ribs; margins are corneous (horn-like) with age, and undulate.
Areoles, that is, the small area bearing spines or hairs on a cactus, are 2 mm (0.079 in) across with internodes 1 to 4 cm (0.39 to 1.57 in). Spines on the adult branches are 1 to 4 mm (0.039 to 0.157 in) long, being acicular (needle-like) to almost conical, and grayish brown to black in colour and spreading, with a deep green epidermis.
- Flowers
The scented, nocturnal flowers are 25 to 30 cm (9.8 to 11.8 in) long, 15 to 17 cm (5.9 to 6.7 in) wide with the pericarpel 2.5 to 5 cm (0.98 to 1.97 in) long, about 2.5 cm (0.98 in) thick, bracteoles ovate, acute, to 2.5 to less than 4 cm (1.6 in) long; receptacle about 3 cm (1.2 in) thick, bracteoles are linear-lanceolate, 3 to 8 cm (1.2 to 3.1 in) long; outer sepals lanceolate-linear to linear, acuminate (tapering to a point), being 10 to 15 cm (3.9 to 5.9 in) long, 10 to 15 mm (0.39 to 0.59 in) wide and mucronate (ending in a short sharp point). Their colour is greenish-yellow or whitish, rarely rose-tinged.
These outer tepals, or sepals are about 65 in number, and bring the flower to a total width of up to fourteen inches (35 centimeters). inner tepals are lanceolate (tapering to a point at the tip) to oblanceolate (i.e. more pointed at the base), up to 10 to 15 cm (3.9 to 5.9 in) long about 40 mm (1.6 in) wide at widest point, and mucronate, unbroken, sharp to acuminate (pointed), and white.
Stamens 5 to 10 cm (2.0 to 3.9 in) long, are declinate, inserted in one continuous zone from the throat to 35 mm (1.4 in) above the pericarpel and cream. The style (bearing the stigma) to 17, they are 5 to 24.5 cm (2.0 to 9.6 in) long, stout, 6 to 8 mm (0.24 to 0.31 in) thick, cream, and up to 26 stigma lobes, they can be whole or sometimes split at the top, cream, about 25 mm (0.98 in) long. Nectar chambers are 30 mm (1.2 in) long.
- Fruit
The fruit is oblong to oval, 6 to 12 cm (2.4 to 4.7 in) long, 4 to 9 cm (1.6 to 3.5 in) thick, red with large bracteoles, with white, or more uncommonly, pink pulp and edible black seeds.
Selenicereus undatus is lithophytic or hemiepiphytic. It is widely distributed through the tropics in cultivation. It is a sprawling or vining, terrestrial or epiphytic cactus. They climb by use of aerial roots and can reach a height of 10 meters (32.8 feet) or more growing on rocks and trees.
II. How to Grow and Care
Sunlight
Although dragon fruit plants enjoy warm weather and are often planted in full sunlight, too much intense sun in dry and especially hot regions causes stem damage. If temperatures in your area are frequently near 100 degrees F, it’s best to plant your cactus in a spot with partial shade. Too much shade, on the other hand, typically results in less abundant fruit production and the quality of your harvest may not be as impressive.
Temperature and Humidity
Dragon fruit plants are native to tropical regions, they won’t survive in areas that experience freezing weather, especially if that freeze is prolonged. Temperatures ranging from 65 degrees F to 80 degrees F at the highest are considered optimal growing conditions.
Watering
Although the dragon fruit plant has some drought tolerance, to produce a good fruit crop, it’s best to water it consistently from the beginning of the bloom to harvest. However, excessive watering risks root rot and various forms of fungal disease. During the winter and into early spring, give the plant less water.
Soil
Dragon fruit cacti are not terribly fussy when it comes to soil type or pH level. The key is that the soil is moist, rich in organic matter, and well-draining. Mulch around the base of the plant—especially in drier regions—to help the soil retain its moisture.
Fertilizing
Dragon fruit cacti are fast growers and heavy feeders. During their first year, fertilize them every couple of months with a complete balanced fertilizer, ideally one with a high nutrient content, such as 20-20-20. Once the plants are well-established, they should do fine with just a couple of fertilizer applications in the spring and summer. In addition, amend the soil with compost or organic matter a couple of times a year.
Planting Instructions
Dragon fruit cactus is best planted in the early spring to take full advantage of its growing season from March to August.
To successfully grow your own dragon fruit plant, you need a location with well-drained soil in full sun to partial shade and ample space. This is a large, heavy cactus with a spreading habit and long stems. Make sure to plant it 15 to 25 feet away from your home and other structures, trees, and electrical lines.
Dig a hole that is 3 to 4 times in diameter and 3 times as deep as the nursery container (this loosens up the soil and aids in root development). Refill the hole with enough soil so that when you place the plant in the hole, it is at the same level as it was in the container.
Space plants at least 6 feet apart and support them with a strong trellis.
Pruning
Pruning your dragon fruit cactus is key to minimizing the risk of fungal disease and insect infestation. Uncontrolled growth also leads to poor light penetration for the tangled center stems, which impacts fruit production. Regular pruning also encourages prolific flowering and prevents the plant from becoming too heavy for the trellis.
Plan to periodically cut back any overly long, damaged, tangled, or dead stems as often as two or three times per year. If you’re lucky (or have a younger plant), you may be able to get away with a
single annual pruning session after you have harvested the fruit.
Propagation
Propagating dragon fruit from stem cuttings is easy and yields fast results, unlike propagation from seed, which is not recommended because it takes up to seven years before the plant starts bearing fruit.
Here is how to use stem cuttings to make a new plant:
- Take a 10- to 12-inch cutting from a healthy stem. Treat the cut end with fungicide.
- Let the cutting callus over in a dry, shady place for 7 to 10 days.
- Dust the cut end with rooting hormone and plant the cutting cut-side down in a pot filled with a well-draining potting mix.
- Water it lightly and keep it moderately moist. Once the cutting has started to root (check by gently tugging on it), gradually move it to a location with more sunlight. It will take the cuttings 4 to 6 months to develop a good root system, after which they are ready for planting in the landscape or larger pots.
- When planted from a cutting, you may have a harvest within one to three years.
Potting and Repotting
A mature dragon fruit plant requires a 25- to 30-gallon size container with a depth of 20 to 24 inches. Given the fast growth rate of the plant, it will require frequent repotting to a larger container with fresh potting soil whenever the plant becomes root-bound. Keep in mind that the roots of the plant are very small and hairy and repotting it requires extra caution in order not to damage them.
Overwintering
Overwintering measures are only necessary below USDA zone 10, where dragon fruit plant can be grown in containers. Bring the plants indoors when daytime temperatures drop below 65 F and there is any danger of frost. In the spring, wait until all danger of frost is past and the daytime temperatures are consistently above 70 degrees F.
In fall and winter, reduce the watering, as the plant goes dormant.
Pests and Diseases
Depending on where you live, wild animals could find your dragon fruit crop appealing. You may need to take measures to protect your cactus and its fruit from rats, raccoons, birds, and more. The plants are also attractive to ants, mealybugs, mites, and thrips.
Potential diseases are stem rot or canker, reddish-brown, yellowish, or white spots and lesions on the stems and blades (leaves). Rot and canker can be difficult to contain on a dragon fruit plant. Remove the damaged, infected parts and treat the plant with a fungicide. To avoid these types of issues, ensure your plant gets the right amount of sun, moisture, and air circulation.
III. Uses and Benefits
The main use of Selenicereus undatus is for its fruit, which has a sweet, mild flavor and a unique, attractive appearance. The fruit can be eaten fresh, added to smoothies or desserts, or used to make jams and other preserves. The plant is also grown for its ornamental value, with its unusual growth habit and striking flowers adding interest to gardens and indoor spaces.
IV. Harvesting and Storage
You will know your dragon fruit is ready to harvest when the flaps on the pink outer skin starts to develop a withered appearance. If it’s ripe, you should be able to twist it from the stem with ease. Any fruit that has fallen from the stem on its own tends to be overripe, so timing your harvest properly is important. If kept in the refrigerator, dragon fruit lasts up to two weeks.
The large, edible flowers that are produced by the cactus are also impressive—they tend to be white and have a strong fragrance. However, they are usually nocturnal, so you’ll only get to enjoy (and pick) them once the sun has gone down.
