Hylocereus monacanthus or Selenicereus monacanthus belongs to the Cactaceae family. It has its origins in various places in Central and South America, some of which include Colombia, Ecuador, Costa Rica, Panama, Peru and Venezuela.
This cactus plant has long cylindrical stems that tend to curve downward. The flowers of this plant are distinctive and tend to grow in small yellow and white cups. The fruits are additionally pink-red in color.
13 Types Of Hylocereus Cacti [With Pictures]
How to Care for Hylocereus monacanthus
Hylocereus monacanthus cacti grow well in controlled conditions, which is why they’re grown and sold commercially around the world. Here’s some information if you’re planning to grow them at home.
Hylocereus monacanthus cacti require full sunlight, especially during their blooming months. Too much shade will result in improper blooming.
If the temperature is moderate, you can expose the plant to direct sunlight; if temperatures are high—over 80°F—you will need to place the plant in partial shade (50-60% shade).
Hylocereus monacanthus cacti can tolerate up to 125°F when partly shaded, but exposing them to at least 40% direct sunlight is essential for robust plants and fruit.
As a member of the cactus family, Hylocereus monacanthus don’t need too much water, but watering them properly is essential.
This means that the water needs to drain well through the soil, instead of pooling or accumulating on the soil surface or at the bottom of the pot.
Water Hylocereus monacanthus only when the soil is dry to the touch so that it is moist again and not soaked, and make sure that excess water drains properly from the plant.
Especially during the fruiting and flowering season, water the plant over 3-7 days, keeping the soil moist, and during the winter and non-flowering/non-fruiting months, watering once a month is sufficient.
Again, like any cactus, Hylocereus monacanthus requires well-draining, organic, sandy soil with a pH between 6.1 and 7.5 so that the soil is slightly acidic.
Hylocereus monacanthus thrives in sandy soil, but if sandy soil is unavailable, any well-draining soil mixture will do. Alkaline soil may result in nutrient deficiencies in the plant and its fruit, but salty soil is tolerated well.
Fertilizing is required only during the active growing season. An organic fertilizer, with moderately high nitrogen content, should be fed monthly to the plant during its growing season.
Do not fertilize during the blossoming season or the cold winter months.
Spreading organic mulch over the root zone is a great way to keep roots from extreme temperature fluctuations and reduce moisture evaporation.
Hylocereus monacanthus requires temperatures above 40°F to prevent any damage from occurring to the plant. Ideal temperatures are between 65 and 80°F, which explains why the plant prospers in tropical and subtropical climes.
Dragon fruits are quite prone to aphids and mealybugs, both pests that feed on the plant’s sap. Mites and thrips can also cause problems, as well as ants (especially if aphids are around, as aphids attract ants).
Fungal infections can also be a problem, causing brown spots to appear on the stem’s surface, whereas bacterial infections cause soft stem rot, aggravated further by nitrogen and calcium deficiency.
Root rot can occur from overwatering and sunburn can kill the plant.
Since it’s a climbing cactus vine, the Hylocereus monacanthus requires support while growing. The side branches that emerge from newly planted stems need to be removed till the time when the plant is tall enough to reach the trellis.
Support the plant with a thick rope till it can support itself. Once the plant is tall enough to reach the trellis’s top, cut the stem to encourage lateral branching.
Ensure that all dead, diseased, and damaged parts are removed and cut parts that reach the soil. Also, stems that cause crowding or interfere with the harvesting can be cut.
Plant this cactus in enriched soil that drains well, with 50-60% shade during the day or as and when needed, as mentioned earlier.
Use a post-and-top frame to support the stem (it should be able to support 250 pounds, the maximum stem weight); avoid using wires as they cut into the plant as its weight increases. Ensure that each seedling is at least 8 inches apart.
Hylocereus monacanthus can also be grown in containers placed on tall posts so that the stems can hang down instead of climbing up. Remember, though, that you’ll need to move the plants indoors during winter—they can get quite heavy, so plant according to your convenience.
A pot is ideal, as it lets you easily move the plant around. Use a large pot (at least 15 gallons) that drains well.
Repotting is not necessary unless your plant gets too big for the pot or container or you suspect root rot.
Propagating Hylocereus monacanthus
The Hylocereus monacanthus grows during the summer and blooms between July and October. The beauty of the plant is that it flowers only one night a year, but after this, fruits begin to form, with one plant producing fruit for 20-30 years!
Therefore, propagating Hylocereus monacanthus is a great idea.
You can propagate them directly, using seeds from the fruit. Cut the fruit in half, scoop out the seeds, separate them from the flesh by washing them, and leave them to dry overnight.
Plant the seeds close to the soil top, ensuring that the soil is moist. Use a plastic film to cover the soil until germination occurs (usually within 15 days). After this, you can transplant the plants into a larger container.
Cuttings are another way to propagate Hylocereus monacanthus. Just ensure that the cutting doesn’t come from the parent plant, as this can stunt growth and harm the plant.
Additionally, start cultivating the cutting during the plant’s growing months, i.e., the summer. A foot-long segment is sufficient, giving you 3-4 new plants.
Divide the cutting into smaller 3-inch pieces, dry/cure them well (generally takes 2-5 days; the whitening of the tips is a sign that the cutting is ready), and then place them in the soil.