Origin and Habitat: Mammillaria zubleraeSN|17623]]SN|17623]] is endemic to Mexico, where it occurs between the towns of Tula and Ocampo in the state of Tamaulipas. It has a very small range (extent of occurrence 270 km², area of occupancy 25 km²). The original population still exists, consisting now of a dozen of plants, including some big clumps. For many years it was only known from this place, it also occurs in several other places, up to 50 km to the north. Total population size is less than 2,500 mature individuals, with each subpopulation having less than 250 individuals.
Altitude range: This species grows at an altitude of 1,200-1,600 metres above sea level.
Habitat and Ecology: Mammillaria zubleraeSN|17623]]SN|17623]] grows on vertical limestone rocks in dense tropical deciduous mixed oak-tropical forest, but only on big rocks that allow the plant to drain the heavy rains that occur in the region. It is an uncommon species and should be considered as threatened in all its distribution range. Illegal collection of the species has probably resulted in population declines.
Synonyms:
See all synonyms of Mammillaria prolifera
Description: Mammillaria zubleraeSN|33265]]SN|17623]] is a small branching cactus species that may form large clusters. Given enough sun in cultivation, the plants develop a compact globular shape with strong golden central spines. Meanwhile plants cultivated in poor light conditions have the tendency to grow large and with slender whitish or pale yellow spines. This is a good species which was considered by Hunt in the 1990 ́as being related to the Mammillaria proliferaSN|9161]]SN|9303]] complex, but certainly the plant has more affinity with Mammillaria vetulaSN|9303]]SN|9161]] known from Hidalgo State. Recently it was re-described as Mammillaria cielensisSN|17623]]SN|33265]] by Martínez-Avalos et al. (2011), which is merely a growth form of the species found in the northernmost parts of its distribution range, coming from shaded and humid places.
Derivation of specific name: zublerae For Ruth Zubler, Swiss cactus enthusiast in Breisach near Basel who discovered this plant in 1981.
Stems: Globose to cylindrical to club shaped, green, 2-5 cm high, 2-4.5 cm in diameter.
Tubercles: Cylindrical to conical, soft, without latex, axils with yellowish wool.
Central spines: 5-6, slender, needle-like, straight, pubescent, glassy yellow, 5-9 mm long.
Radial spines: 20-24, fine, bristle-like, straight or curving, white with yellowish tips, 4-7 mm long.
Flowers: Clear yellow, to 15 mm long and in diameter.
Fruits: Bright red.
Seeds: Black.
Subspecies, varieties, forms and cultivars of plants belonging to the Mammillaria prolifera group
Bibliography: Major references and further lectures
1) Pilbeam, J. 1999. “Mammillaria”. Cirio Publishing Services, Southampton.
2) Hunt, D., Taylor, N. and Charles, G. (compilers and editors). “The New Cactus Lexicon.” dh Books, Milborne Port, UK. 2006.
3) Fitz Maurice, B & Fitz Maurice, W.A. 2013. Mammillaria zublerae. The IUCN Red List of Threatened Species 2013: e.T152813A681664. http://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T152813A681664.en. Downloaded on 29 November 2016.
4) Urs Eggli, Leonard E. Newton “Etymological Dictionary of Succulent Plant Names.” Springer, Berlin/Heidelberg 2010
5) Leccinum J. García Morales “The Golden Mammillarias of Tamaulipas, México” Xerophilia – Vol. 2, No. 2 (5) – June 2013
Cultivation and Propagation: Mammillaria zubleraeSN|17623]]SN|17623]] is a freely clustering species that reproduces easily by cutting, recommended for any collection that needs lots of light with ample airflow. Given the kind of care used on any but the desert forms of cacti, even in a small pot, this little cactus will grow and proliferate its small heads into an interesting cluster.
Growth rate: It is a small growing, but easily flowering species. It offset from the base and can fill a 25 cm pot in just a few years given the best conditions.
Soils: It likes very porous standard cactus mix soil with little organic matter (peat, humus).
Repotting: Repotting every 2-3 years. It will need a pot with sufficient depth to allow the tap root. As it is especially prone to rot under-pot in a smaller container filled with very porous compost. Use pot with good drainage.
Watering: Water regularly in summer, but do not overwater (very wet-sensitively, especially in light of its succulent root system). Its roots are easily lost in pots that stay damp for any length of time. Keep dry with ample airflow in winter. In the rest period no high atmospheric humidity!! Care must be taken with watering as they tends to become swollen and untidy in growth habit if given too much water and shade.
Fertilization: During the growing season enrich the soil using a fertilizer rich in potassium and phosphorous, but poor in nitrogen, because this chemical element doesn’t help the development of succulent plants, making them too soft and full of water.
Hardiness: Reputedly sensitive to frost , but less so if kept on the dry side prior to, and during, cold weather (hardy to -5° C for short periods). However some warmth throughout the year will increase the grower's success (minimum 5° to 8°C during rest season).
Exposition: Outside bright sun, filtered sunlight or afternoon shade, inside it needs bright light, and some direct sun. Subject to sunburn if exposed to direct sun for too long. Tends to bronze in strong light, which encourages flowering and heavy wool and spine production.
Uses: It is an excellent plant for container growing. It always looks good and stays small. It look fine in a cold greenhouse and frame.
Pests & diseases: It may be attractive to a variety of insects, but plants in good condition should be nearly pest-free, particularly if they are grown in a mineral potting-mix, with good exposure and ventilation. Nonetheless, there are several pests to watch for:
- Red spiders: Sensitive to red spider mite. Overhead watering is helpful in controlling mites.
- Mealy bugs: Occasionally mealy bugs they develop aerial into the new growth among the wool with disfiguring results, but the worst types develop underground on the roots and are invisible except by their effects.
- Scales: Scales are rarely a problem.
- Rot: Rot it is only a minor problem with cacti if the plants are watered and “aired” correctly. If they are not, fungicides won't help all that much.
Propagation: Direct sow after last frost or (usually) cuttings. Seeds germinate in 7-14 days at 21-27° C in spring, remove the glass cover gradually as the plants develops and keep ventilated, no full sun for young plants! The seedlings should not be disturbed until they are well rooted, after which they can be planted separately in small pots. Cuttings: wait until the offsets that appear at the base of old clustered specimens are 1/3 the size of the parent and then detach and plant. Cuttings will take root in a minimum temperature of 20° C (but better in hot weather). Cuttings of healthy shoots can be taken in the spring and summer. Cut the stem with a sharp, sterile knife, leave the cutting in a warm, dry place for a week or weeks (depending on how thick the cutting is) until a callus forms over the wound. Once the callus forms, the cutting may be inserted in a container filled with firmed cactus potting mix topped with a surface layer of coarse grit. They should be placed in the coarse grit only; this prevents the cut end from becoming too wet and allows the roots to penetrate the rich compost underneath. The cuttings should root in 2 to 6 weeks.