Hatiora
Hatiora is a small genus of epiphytic and lithophytic cacti native to the forests of eastern Brazil. Its members are shrubby, freely branching plants that hang or clamber over trees and rocks, and the genus includes the curious, jointed dancing bones or drunkard's dream (Hatiora salicornioides), as well as the showy Easter cactus — long grown under Hatiora but now usually placed in the segregate genus Rhipsalidopsis. Like the closely related Schlumbergera (the Christmas and Thanksgiving cacti) and Rhipsalis, Hatiora belongs to the tribe of jungle cacti rather than the spiny desert dwellers most people picture.
Description
Hatiora are shrubby, much-branched cacti whose stems are divided into distinct segments, or joints. In the type group these joints are small, cylindrical and often club- or bottle-shaped, strung together like beads and giving the plants a delicate, spilling habit. In the Easter-cactus group (now generally treated as Rhipsalidopsis) the segments are flat and leaf-like, closely resembling those of Schlumbergera.
The plants are essentially spineless, bearing only fine bristles or wool at the areoles rather than true spines. Small flowers appear at the tips of the youngest segments — yellow to orange in the cylindrical-stemmed species, and larger, radially symmetrical, pink to red blooms in the Easter-cactus group. Flowering typically follows the cooler, shorter days of winter into spring. As epiphytes, the roots are modest and adapted to the fast-draining, organic pockets of debris that collect in tree forks and rock crevices.
Distribution and habitat
The genus is endemic to Brazil, where it grows in the humid coastal Atlantic Forest and the mountains of the southeast. Plants live as epiphytes perched on tree branches and as lithophytes anchored to shaded, mossy rock faces. These are habitats of high humidity, bright but filtered light, and free air movement — conditions quite unlike the arid homes of most cacti, and a useful guide to how the plants like to be grown.
Taxonomy
The circumscription of Hatiora has shifted considerably over the years. The flat-stemmed Easter cacti were for a long time included here (as Hatiora gaertneri and Hatiora rosea and their hybrids), but molecular work has led most authorities to separate them once more into the genus Rhipsalidopsis. The name Hatiora is an anagram of the earlier name Hariota, which honoured the English mathematician and naturalist Thomas Hariot. Older literature and plant labels frequently use the two names interchangeably, so gardeners will encounter both.
Notable species
- Hatiora salicornioides — the dancing bones or drunkard's dream, with slender, bottle-shaped joints and small yellow flowers; the best-known species in cultivation.
- Hatiora gaertneri — the Easter cactus, flat-jointed with vivid red spring flowers (now often Rhipsalidopsis gaertneri).
- Hatiora rosea — a smaller, pink-flowered Easter cactus and an important parent of garden hybrids (now often Rhipsalidopsis rosea).
- Hatiora epiphylloides — a rare, diminutive species with tiny flattened segments.
Cultivation
Hatiora are grown much like their relatives Schlumbergera and Rhipsalis, and reward treatment that reflects their forest origins rather than the dry regime given to desert cacti. Provide bright but filtered light — an east-facing window or lightly shaded spot suits them, while harsh midday sun scorches the segments. Use an open, airy potting mix with plenty of organic matter and grit so that it holds a little moisture yet drains freely; a mix intended for epiphytes or orchids, lightened further, works well.
Unlike desert cacti, these plants should not be allowed to bake bone-dry for long stretches during active growth. Water moderately when the top of the mix begins to dry, and keep humidity up; they resent both drought stress and soggy, stagnant compost. Many growers find hanging baskets ideal, letting the branching stems cascade. To encourage flowering, give the plants a cooler, drier rest with the longer nights of autumn and winter — this bud-setting period is much the same as for Schlumbergera, and moving buds around at the wrong moment can cause them to drop.
Propagation
Propagation is easy and usually vegetative. Detach a stem segment or short chain of segments, let the cut end callus for a day or two, then set it in a lightly moist, free-draining mix, where it roots readily. This is the same technique used for Schlumbergera and is covered under Propagation — cuttings. Species can also be raised from seed, though this is slower and less common outside specialist collections.
Cultivars and hybrids
Most named garden plants sold as Easter cacti are hybrids within the flat-stemmed group (the Rhipsalidopsis segregate), selected for flower colour across shades of red, pink, orange, apricot and white. The cylindrical-stemmed Hatiora salicornioides is grown more for its quirky, jointed form than for its modest flowers, and remains a popular, forgiving houseplant and a favourite subject for hanging displays.
Common problems
- Rot — the commonest killer, caused by a heavy, water-retentive mix or standing water; stems yellow, soften and drop.
- Bud drop — buds fall before opening if the plant is moved, chilled by draughts, or allowed to dry out during budding.
- Scorch and reddening — segments bleach or flush red-purple in too much direct sun; move to brighter shade.
- Pests — mealybugs (white fluff in the joints and roots) and scale are the usual offenders; see Pests and diseases.
See also
- Rhipsalidopsis — the Easter cacti, formerly included here
- Schlumbergera · Rhipsalis — related jungle cacti
- Hatiora salicornioides — the dancing bones cactus
- Soil and potting mix · Watering · Propagation — cuttings