In what’s shaping up to be the worst drought in recorded Texas history, there’s a few bits of good news. Namely, it’s a remarkably good season for dragonfruit cactus.
The genus Hylocereus is one of the two genera of true cactus raised commercially for food: the other being the prickly pear Opuntia. In the US, two varieties generally appear for sale in Asian markets and high-end grocery stores, and both are sold under the common name “dragonfruit”. It’s not hard to see why, between the color and the scales, as shown below.
The difference between the two is really only obvious when you cut one open. H. undatus has white flesh speckled with tiny black seeds. H. costaricensis, though, is a brilliant red-purple, about the color of fresh pomegranate juice, with the same black seeds. Sometimes it can be hard to tell which variety is which solely based on the rind, but it really doesn’t matter as far as the flavor is concerned. First-time dragonfruit eaters are often disappointed at the seeming lack of flavor in the ripe fruit, as it’s really subtle, but the crunchy consistency makes up for it. (I personally prefer it well-chilled, quartered, and served with the rind on the back of each segment, but it’s also a great addition to fruit salad or smoothies, and dragonfruit jam is apparently quite popular in England. I’ve heard of recipes that involve broiling dragonfruit like grapefruit, but dragonfruit doesn’t last long enough around the house for this to be an option.)
With one big caveat, both commercially available varieties of Hylocereus are very easy to raise in propagation. They can be grown from seed taken from ripe fruit: my best results have come from mashing a chunk of the fruit gently with the flat of a knife, smearing the pulp atop standard potting compost, and keeping the compost moist but not wet. The only real problem with this method is that the resultant seedlings are very slow-growing, and they tend to be rather susceptible to large changes in environmental conditions. A much more dependable method of propagation involves cuttings, and considering how often branches break off, simply putting the cutting atop a pot full of compost can produce a full-sized plant within a year instead of three to four for seedlings. Most branches grow aerial roots whenever the ambient humidity is above 50 percent, so just sink those into the compost and watch the plant take over.
As a potted plant, H. costaricensis makes a spectacular hanging basket. In the wild, Hylocereus climbs trees with the help of those aerial roots clinging to bark, but it also apparently sprouts in the crooks of large trees or rocks and hangs downward. Since it’s a tropical cactus, Hylocereus cannot handle sustained freezes, and should be brought into shelter when the outdoor temperatures drop below 40 degrees F (4.44 degrees C). Since it adapts very well to both standard pots and hanging pots, though, this generally isn’t a problem. The typical cactus spines are both small and fragile in Hylocereus, and don’t appear to set off any sort of allergic reaction, but be cautious all the same. Other than giving it full sun to light shade whenever possible, these cactus are very low-maintenance: I water whenever dry, and fertilize with bat guano about once per month.
Remember the caveat mentioned before about dragonfruit propagation? If you’re planning to grow any Hylocereus, don’t expect the cactus to start blooming until it gets big. Most growers report that the individual plants won’t bloom until they weigh at least 10 pounds (4.53 kilograms), and some varieties may not bloom until the total weight of the plant is over 20 pounds (9.07 kilograms). The good news is that unlike most other cactus, Hylocereus is self-fertile, with some plants producing fruit without being pollinated at all. They’re also apparently capable of producing viable hybrids within the genus, leading to quite the entertaining assortment of cultivar names, ranging from “David Bowie” to “Physical Graffiti”. In addition, the night-blooming flowers are huge, resembling giant white versions of Christmas cactus (Schlumbergera spp.) and very sweet-smelling.
The only complaint I have about raising Hylocereus is minor. Namely, growing them is addictive. Expect to see several plants at next month’s FenCon show, and we can all sing Ministry’s “Just One Fix” together.