Cephalocereus totolapensis
| Light | Bright light to full sun once established |
|---|---|
| Water | Moderate in summer; keep dry and rested in winter |
| Soil | Fast-draining mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 10a–11 |
| Propagation | Seed; cuttings of side branches |
| Toxicity | Non-toxic to cats and dogs |
Cephalocereus totolapensis is a tall, tree-like columnar cactus from southern Mexico that was long known under the name Neobuxbaumia totolapensis. Following the merging of Neobuxbaumia into Cephalocereus, it is now recognised within the genus Cephalocereus. It is a robust, branching species that forms a distinct trunk with age, growing into a small green candelabra of ribbed columns.
Description
Cephalocereus totolapensis is a large columnar cactus that develops a well-defined woody trunk and a crown of erect, ascending branches, giving mature plants a tree-like (arborescent) habit several metres tall. The individual stems are stout, deep green, and divided into numerous ribs running the length of the column.
Areoles set along the ribs carry short spines — a mix of stiffer central spines and finer radials — that are modest in size relative to the bulk of the stem. Unlike some of its relatives, this species does not form the conspicuous woolly flowering cephalium seen in the woollier Cephalocereus; flowers instead open from areoles near the stem tips. The blooms are funnel-shaped and nocturnal, opening in the cooler hours and, as in other night-blooming columnar cacti of the region, visited by bats; they are followed by fleshy fruit.
Distribution and habitat
The species is native to southern Mexico, where it grows in seasonally dry country in Oaxaca; its epithet refers to a locality of that name in the region. It is a plant of tropical dry forest and thornscrub on rocky slopes, sharing this habitat with other columnar cacti and drought-adapted shrubs.
In these habitats the plants endure a long dry season followed by summer rains, and they are accustomed to strong light, heat, and sharply draining ground. As with all cacti, the family is listed under CITES Appendix II; nursery-raised plants are the appropriate source for collectors.
Cultivation
Cephalocereus totolapensis is a straightforward grower for anyone with room for a large columnar cactus. Give it a very free-draining, mostly mineral mix and the brightest position you can offer; young plants appreciate a little shading from the harshest afternoon sun, but established stems take full sun well and colour up best in strong light.
Water moderately through the warm growing season, letting the mix dry out between waterings, then keep the plant dry and cool over winter to prevent rot and harden it against cold. Like most tropical columnar cacti it resents frost, so bring it under cover or indoors where winters dip below freezing. Being a naturally tall species, it benefits from a deep, stable pot and occasional repotting as it gains height. See Watering for general technique.
Propagation
Seed is the usual way to raise this species and gives well-rooted, naturally branching plants; sow onto a warm, mineral surface kept humid until germination (see Propagation — seed). Side branches can also be taken as cuttings: remove a branch cleanly, let the cut surface callus over for a week or more, then set it in a gritty mix to root, as described in Propagation — cuttings.
Common problems
- Rot — the main risk, almost always from overwatering or a slow-draining mix, especially over a cool winter; stems soften and discolour from the base.
- Etiolation — too little light produces thin, pale, weakly-ribbed growth that never firms up.
- Cold damage — scarring or collapse of tissue after exposure to frost.
- Pests — mealybugs (white fluff in the areoles) and red spider mites (fine webbing, bronzed skin) are the usual offenders; see Pests and diseases.
See also
- Cephalocereus — the genus overview
- Soil and potting mix · Watering · Repotting · Propagation — seed · Propagation — cuttings