Turbinicarpus saueri
| Light | Bright light; a little shade from harsh summer sun |
|---|---|
| Water | Very sparingly; allow to dry completely, keep dry in winter |
| Soil | Gritty, mostly mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; a cool, dry winter rest suits it |
| Propagation | Seed (primary); occasionally offsets |
| Toxicity | Non-toxic to cats and dogs |
Turbinicarpus saueri is a small, slow-growing globular cactus from Tamaulipas and San Luis Potosí in northeastern Mexico, clothed in short, pale, comb-like spines and topped in season by white to pale pinkish flowers. It belongs to the group of dwarf Mexican cacti once placed in the genus Gymnocactus, now folded into Turbinicarpus, and is closely allied to species such as Turbinicarpus gielsdorfianus.
Description
Turbinicarpus saueri forms a small, firm body that is usually solitary but may cluster with age, typically only a few centimetres across. The surface is divided into low tubercles, each carrying an areole that bears a spray of short, thin, pale spines — often whitish to greyish and pressed close to the body, giving the plant a neat, softly bristled look rather than a fiercely armed one.
Flowers appear from near the crown in the cooler, brighter part of the year, opening white to a soft pink and small in proportion to the plant. Like others in the genus it has a substantial taproot, an adaptation to its dry native ground that stores water and anchors the plant during drought.
Distribution and habitat
The species is native to Tamaulipas and San Luis Potosí in northeastern Mexico, where it grows in arid scrub and rocky, calcareous ground. Plants often sit low among stones and sparse vegetation, contracting toward the soil in dry spells so that little more than the spined top is visible. As with all members of the group its habitat is limited and localised, and wild populations should never be collected — nursery-raised, seed-grown plants are the responsible source.
The entire genus Turbinicarpus is listed on CITES Appendix I, so international trade in wild-collected plants is tightly restricted; artificially propagated plants are widely and legally available with the appropriate documentation.
Cultivation
Turbinicarpus saueri is a rewarding miniature for the collector but, like most of its genus, unforgiving of excess moisture. Grow it in a very free-draining, mostly mineral mix in a deep-enough pot to accommodate the taproot, and give it bright light with only light shade from the most intense summer sun. Water thoroughly once the soil has dried right out, then wait; keep the plant completely dry through a cool winter rest to firm the body and encourage flowering.
Overwatering and a heavy, water-retentive mix are the commonest causes of loss, since rot readily attacks the taproot. See Watering and Repotting for general technique.
Propagation
Seed is the usual and most reliable method, sown on a warm, gritty surface kept lightly humid until germination; seedlings are slow but not difficult with patience. Where a plant has produced offsets these can be removed and rooted, though clustering is not a strong habit in this species. See Propagation — seed and Propagation — offsets for full walkthroughs.
Because seedlings grow slowly, some growers graft young plants onto a vigorous rootstock to speed them along before returning them to their own roots.
Common problems
- Rot — nearly always from overwatering or a slow-draining mix; the taproot and body soften and discolour.
- Etiolation — too little light makes the body pale and elongate, spoiling its compact form.
- Pests — red spider mites and mealybugs are the usual offenders; watch the crown and areoles (see Pests and diseases).
See also
- Turbinicarpus — the genus overview
- Soil and potting mix · Watering · Propagation — seed · Grafting