Description
Astrophytum capricorne var. crassispinum is a popular variey of “Astrophytum capricorne” characterized by a sharp-ribbed, larger body with bright green and almost bare skin (lacks white dots), but the main distinguishing feature is in the spination. Spines are noticeably stronger, longer, larger and thicker than in the common Astrophytum capricorne.
Crested form: The crested sago palm (Astrophytum capricorne var. crassispinum f. cristata) is a very rare, slow-growing and highly priced crested cactus forming odd shapes. Its stems fan out and can make a spectacular specimen. The crested form - despite to its beauty - is still very rare, pricey and sought after by collectors.
Stem: Fan shaped up to 30 cm in diameter, and c. 10 cm in width.
Ribs: Sharp dull-geen to bluish-green often with a reddish edge.
Areoles: Elongate greyish tomentose.
Spines: The 6-8 (or more) spines are somewhat pectiate, striking strong and up to 8.5 cm long, flat, black to brown in the youth, later grey-chalky. They are noticeably stronger, larger and thicker than in the common Astrophytum capricorne. Yellow spined plant are occasionally found in cultivation.
Flowers: The blossoms have a reddish eye as in Astrophytum capricorne var. niveum but pure sulphurous flowers are also mentioned.
Origin and Habitat
Garden origin.
Cultivation and Propagation
It is not too difficult in a greenhouse, although grows quite slowly. It is usually seen as a grafted plant but can grow on its own roots too.
Soil: Use a mineral well permeable soil with little organic matter (peat, humus).
Exposure: They need a good amount of light shade to full sun this help to keep the plants healthy, although slow growth.
Watering: Water sparingly from March till October (weekly during summertime, if the weather is sunny enough), with a little fertilizer added. Less or no water during cold winter months, or when night temperatures remain below 10° to prevent root loss. It is sensitive to overwatering (rot prone).
Fertilization: Feeding may not be necessary at all if the compost is fresh then, feed in summer only if the plant hasn’t been repotted recently. Do not feed the plants from September onwards as this can cause lush growth which can be fatal during the darker cold months.
Hardiness: Keep perfectly dry in winter at temperatures from 5 to 15 degrees centigrade. (but it is relatively cold resistant and hardy to -5° C, or possibly colder for short periods) In the rest period no high atmospheric humidity!! (Temperature Zone: USDA 9-11)
Crested growth: Unlike ‘monstrose’ varieties of plants, where the variation from normal growth is due to genetic mutation, crested growth can occur on normal plants. Sometimes it’s due to variances in light intensity, or damage, but generally the causes are unknown. A crested plant may have some areas growing normally, and a cresting plant that looks like a brain, may revert to normal growth for no apparent reason. If you have any of the crested part left you need to remove the normal growth and leave the crested part behind this will need to be done regularly.
Propagation: Seeds, grafting or cuttings. Seeds usually will not come true to the crested shape of the parent and generate normal 8 ribbed plants. Plants are often grafted onto column-shaped cacti but proved to be able to produce their own roots if degrafted. 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. Large crested piece must be placed on the soil surface without burying the plant base down in the soil.