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Astrophytum myriostigma
Common Name(s): bishop' s miter, bishop' s cape; Mexican names: birreta of obispo, bonete, mitra
Stalk: Globular to cylindric up to 60(-100) cm tall (but usually about 150 cm tall) and 10-20 cm in diameter, bright green, covered with many minute white hairy scales that give it a characteristic chalk-white or silvery-grey appearance, but sometime naked. The scales are composed of very fine interwoven hairs, which, under a microscope, are very pretty object.
Ribs: Usually 5, sometimes 4 (3). With age they increase to 8 or more
Areolas: Closed together The areoles in the older plants are quite different from those of juvenile specimens. They are large, very woolly,  often brownish/reddish (but variable in colour from white/ yellowish to tan/black) and showy.
Flowers: The glossy yellow, sweet scented flowers appear continuously during the summer 4 – 7 cm long
Fruits: reddish fruit, 1 inch in diameter (2.5 cm).
Water Needs: regular water throughout the summer. Keep dry as soon as the temperature starts dropping in October.
Cultivation: it is one of the easier Astrophytum to grow. The Astrophytum myriostigma grows much faster with a low nitrogen content fertilizer in spring and summer.
Min Temperature: 50°F (10°C); Frost Tolerance: Hardy to 20°F (-6°C) for short periods
Propagation Methods: Almost exclusively by seed. Plants are sometimes grafted onto column-shaped cacti. Cutting scions from a flourishing plant is almost a crime because the scions do not root easily

Astrophytum myriostigma Japanese cultivar ONZUKA

Super Kabuto:
 the origin of the most famous Japanese cultivar is still quite unclear  there are several versions of its discovery.  The official version is that of Tony Sato and partly transcribed in the Astrobase (in English and German).
 The mother plant was found in 1981 by a Japanese (Masaomi Takeo) in a nursery in the United States.  The Astrophytum was in very poor condition, abandoned in a corner of the nursery.  Despite the poor health of the plant, Mr. Takeo notes that it has developed large white dots in unusual asterias.  This plant is a natural mutation occurred in a seedling seed habitat

Super Kabuto cultivar differs from the type species by its more dense with flaking white spots larger and fluffy. For cons, the areolas remain the same asterias. This cultivar is smaller, with a maximum of 8-10 cm in diameter.The epidermis is a tendency to split, which is inconvenient for the aesthetics of the plant.

 Mr. Takeo quick to bring it back to Japan where he manages to do it again take root and flower the same year.  Cross with his collection of classic asterias, it gets a hundred seeds and get 30% of seedlings with large white spots characteristic of the parent plant.
 Tony Sato, Japanese producer of cactus, buys the mother plant and all its seedlings Super Kabuto he calls "the Super Asterias!" 
Cv.  Super Kabuto is of mixed mutant plant native habitat with asterias type, which explains the high variability encountered in this cultivar.
Description:  Super Kabuto cultivar differs from the type species by its more dense with flaking white spots larger and fluffy.  For cons, the aureola remain the same asterias.  This cultivar is smaller, with a maximum of 8-10 cm in diameter.  The epidermis is a tendency to split, which is inconvenient for the aesthetics of the plant.

Astrophytum myriostigma variant quadricostatum

Within the natural range of myriostigma, there is no population where the number of ribs is stable throughout the life of the plant. This species has indeed the characteristic form new rib during its development. 4 or 5 ribs in the seedling stage, the cactus will gradually increase to 6-7 adults or 8 ribs as it grows. Some are hesitant and produce quickly abort ribs, giving an appearance of "beak". But it is rare that the number of ribs does not change. However, it is the myriostigmas of "Jaumave" that tend to keep longer look quadricostatum acquired as juveniles.
We can not therefore speak of 'variety' based on the number of ribs, but only a 'form' as this character is not stable.
The most common among myriostigma is to have 4 or 5 ribs but it is common to count up to 8 with extreme values ​​from March to November!
To avoid the formation of new coastline, these precious myriostigma are grown in a very poor substrate by reducing watering.

Astrophytum ornatum

Common Name(s): Star Plant, Monk's Hood
Description: Ornatum is the biggest kind of Astrophytum. First of all globular, he takes a columnare form fast.
Stalk: Spherical when young, than become shortly columnar. Up to 4 feet tall (1.2 m), 12 inches in diameter (30 cm); covered with white flecks that ornate the stalk. Some exemplars lose the scales with age. Some plants have twisted ribs
Ribs: usually 8. But with age up to a maximum of 11.
Spines:
Central (S): 1 over 1 inch (2.5-4.0 cm) long strite, brownish yellow 
Radial (S): 5 to 10, amber yellow, later brown and finally grey. 
Areolas: At first yellowish-white felted, later glabrous.
Flowers: 2.5 inch (6 cm) wide; Blooming time: med Spring up to late Summer. Color – bright yellow. Seedlings take 5 years to bloom.
Fruits: Hairy fruit
Water Needs: Water regularly; do not over water
Sun Exposure: Full sun to partial Shade
Cultivation: Easy to grow. It needs to be at least 15 cm tall to bloom .
Soil: Soil mix should have a good drainage and also must have deterrent properties.
pH requirements: 5.1 to 5.5 (strongly acidic) 5.6 to 6.0 (acidic).
Reader can use the “Cactus and Palm mix” that can be found in Garden Centers.
Propagation Methods: From woody stem cuttings allow cut surface to callous over before planting
From seed; sow indoors before last frost, or direct sow after last frost. From seed; germinate in vitro in gelatin, agar or other medium
Frost Tolerance: Hardy to 20° F (-6°C)
Copiapoa tenuissima
Origin: Northern Chile
Recommended Temperature Zone: USDA: 10b-12
Growth Habits: Slowly clumping, heads up to 1.5 inches in diameter (4 cm)
Description: Small growing and easy to to flower has a naturally dark body with nicely contrasting bright yellow flowers.
Single headed or slowly clumping, usually at or slightly below soil level.
Stem: Up to 5 cm in diameter, flattened to spherical, dull-green, dark olive green, to almost purplish-black. The stem is tuberous rather than ribbed stem
Flowers: Pretty, yellow diurnal, up to 2.5 cm long. Tepals up to 15 mm long 5-7 mm wide. Ovary with pubescent scales, floral tube 4-7 mm long. The flowers are supposedly to be sweet scented.
Bloom Time: Mid Spring,Late Spring/Early Summer,Mid Summer,Late Summer/Early Fall. In cultivation in the C. tenuissima are able to flower from immature stems at an early age (c. 2 years from germination) and set viable seed.
Sun Exposure: Light shade to full sun
Water Needs: Keep fairly dry in winter, water moderately in summer
Cultivation: Need full sun otherwise the bodies tended to elongate in cultivation, but should be protected from excessive heat and sun in summer, Require light watering, good drainage, and deep pot to accommodate tap root. Keep warm and dry in winter to avoid rot.
Frost Tolerance: Avoid any frost
Propagation Methods: Heads can be used as cuttings. They grow slowly at first until they develop the large tuberous root. Grafting is also used to speed growth rate and to create a back-up to plants in collection.
Drought-tolerant; suitable for xeriscaping;Average Water Needs; Water regularly; do not over water;Suitable for growing in containers

Echinocactus grusonii
Common Name(s): Golden Barrel Cactus, Golden Ball Cactus, Mother-in-Law's Cushion, Mother-in-law's-seat  
Origin: native to central Mexico
Description: Growing as a large roughly spherical globe, it may eventually reach over a meter in height after many years. The young seedlings like the other Echinocactus and Ferocactus seedlings, the rib structure is not yet apparent, and they have pronounced tubercles making them look superficially like Mammillarias.
Stalk:  is pale green
Ribs: There are 35 ribs in mature plants, but young plants have tuberous app
Spines: straight golden yellow radial spines
Flowers: 1.5 to 2 inches (4-5 cm) yellow flowers; blooming from end of March to end of July.
Sun Exposure: Full sun to partial sun
 Water Needs: Water generously in summer; less watering in winter.

Cultivation: Widely cultivated in warmer climates around the world, it is considered easy to grow and relatively fast growing. It has been increasingly used as an architectural plant in garden design
E. grusonii are summer-growing and pretty easy plants to cultivate. They are suited for any rich, well drained soil such us clay, pumice, lava grit, and only a little peat or leaf-mould. If potted, repot preferably in the spring, if their roots become cramped.  Generally, they should be repotted every other year in order to provide fresh soil. However, this doesn't necessarily mean they'll need larger containers. Fill about a quarter of the pot with broken crocks, gravel, etc. to promote good drainage. After repotting, do not water for a week or more. Water regularly during the growth cycle (this plant need plenty of water, but do not over water and let their soil dry out between watering), and also needs to be avoided wetting the body of this plant while it is in sunlight. A wet cactus in the sun light can cause sun burning which can lead to scares or even fungal infections and death, keep rather dry in winter. No water should ever be allowed to stand around the roots. Feed with a high potassium fertilizer in summer. (cactus-art.biz)
 Min Temperature: 55°F (12°C) Frost Tolerance: Hardy to 14° F (-10°C) for short periods

Epithelantha micromeris

Common Name(s):  Button Cactus, ping-pong ball cactus, Common button cactus.
Recommended Temperature Zone: USDA: 8b-11
Description: The rather small flowers are often followed by attractive red fruits which contrast nicely with the spines. Miniature globose cactus, erect, un branched or in small clumps, not deep-seated in substrate, appearing ashy grey and relatively rough in general aspect
Stem: Unsegmented, mostly spheric or obovoidal, rarely cylindric, often flat-topped with a depressed centre, 1-5(-9)cm tall and up to 2-4 (-7,5) cm in diameter, occasionally more; surface completely obscured by spines; cortex and pith are not mucilaginous.
Tubercles: Numerous, not confluent into ribs, hemispheric or short cylindric, very small, ca. 1-3 mm; arranged in tight spirals around the plant.
Spines: Small at tips of tubercles, 1 mm long, nearly circular, elliptic when distended by flower or fruit, slightly woolly when young, copiously woolly only at sexually mature stem apex; areolar glands absent.
Areolas: Small at tips of tubercles, 1 mm long, nearly circular, elliptic when distended by flower or fruit, slightly woolly when young, copiously woolly only at sexually mature stem apex; areolar glands absent;
Roots: Diffuse (usually) or tap-root (in some populations)  also tuberlike (see: E. pachyriza )
Flowers: The Button Cactus has 0.2 inch long (5 mm), 0.16 inch wide (4 mm) pale pink flowers that appear in May-June at the apex of the plant. They only partly opens, as they barely stick out above the wool an spines at the top of the plant.
Fruits: thin red fruit, 0.3 to 0.5 inch long (8-12 mm).
Sun Exposure: Light shade to full sun
 Water Needs: Moderate water. The Button Cactus needs a soil mix draining particularly well, since it needs a deeper pot due to its tap root.
Cultivation: Although regarded as a choice and difficult plant, in cultivation it is relatively easy. It needs a  particularly well-draining soil mix (rot prone). Water sparingly.
Min Temperature 50°F (10°C)
Frost Tolerance: Depending on the variety, will take 10° F (-12° C)
Propagation Methods: Seeds
Psychoactivity: The Epithelantha contains hallucinogenic alkaloids.

Ferocactus latispinus

Common Name(s): Devil's Tongue Barrel, Crow's Claw Cactus

Etymology: Ferocactus: From the Latin word ferox, meaning fierce and the Greek word kaktos, meaning thistle. Latispinus: From the Latin words latus, meaning broad or wide and spina, meaning thorn or prickle.

Description: Globular cactus. Ferocactus latispinus is fairly popular in cultivation because it blooms very early, many young plants will bloom when they reach 4 inches in diameter (10 cm).

Stalk: 10 to 16 inches in diameter (25 to 40 cm);
Ribs: 14 to 23 ribs

Spines:
Central (S): 4 large central spines, the lowest central is wider
Radial (S): 6 to 12 1-inch long radials                                                    Flowers: pinkish purple or yellow flowers, 1 to 1.5 inches in diameter (2.5 to 3.5 cm). They come in late autumn to early winter, and need a fair amount of bright sunlight to form.                                                                              Water Needs: Little to moderate water when established                              Min Temperature: 50°F (10°C); Frost Tolerance: Hardy to 25°F (-4°C)

Ferocactus rectispinus

Common Name(s):  Long Spined Barrel Cactus, Straight Spine Barrel
Description: this magnificent plant has some of the longest straightest spines of the Ferocacti.
Stalk: Erect, globular when young to a stout cylinder when older, 30-200 tall × 30-60 cm in diameter; tubercled when young later forming ribs. 
Ribs: 15-21, shallowly notched immediately above each areole.
Spines: New spines are bright red
Central (S): 1, very long ( 9-25 cm long × 2.5-4 mm. in cross section ), never hooked (or slightly hooked, but only on relatively young plants), roughly cylindrical, annulated, all robust and rigid. Reddish, reddish grey, or horn colored.
Radial (S): 5 to 9, spreading, not hooked, 2.5 to 7 cm long, with the upper 3 larger. 
Areolas: Oval with brown wool, 3-4 cm apart.
Flowers: Large, light yellow,  6-7.5  long× 5-7.5 cm in diameter: Blooming in the Summer
Fruits: Persistent, oblong, scaled, 2,5-5cm long × 25-35 mm long in diameter with the dried remains of the flower atop, ± readily dehiscent through basal pore, bright yellow.
Seeds: 2 mm. in diameter, black
Sun Exposure: Full sun to light shade
 Water Needs: Little to no water when established; when the plant vegetate it needs watering when the blanket of soil is dry. 
Min Temperature: 50°F (10°C); Frost Tolerance: 25°F (-4°C)
Propagation Methods: from Seeds

Gymnocalicyum denudatum v. brasiliensis

Common Name(s): Spider Cactus (The name Spider Cactus refers to the shape of the white spider-like spines.)
Description: This species has nearly armless spines flattened against body, looking like a bunch of white spiders crawling on a cactus.
Stalk: Small globular usually unbranched cactus with glossy dark green body and rounded ribs (The 'chin' effect is not as visible as other Gymnocalycium)  Grows up to 15 cm in diameter and 10cm tall. 
Ribs: 5-8
Spines: Nearly harmless spines flattened against body in shape of small, white spiders. White, 5-8, up to 2 cm long
Flowers: Large cream white, those are up to 7 cm wide. Blooming time:  In spring and summer
Sun Exposure: Full sun to light shade.
Cultivation: very easy to grow, this plants offers no cultivation difficulties. Summer grower needs moderate to copious watering in summer. Quite frost resistant if kept dry in winter -4° C.  Feed with a high potassium fertilizer in summer.
Propagation Methods: Seeds (seldom produces offsets)
 

Pelecyphora pseudopectinatus

Recommended Temperature Zone: USDA Zones 9-11
Description: Solitary, globular depressed, 20-30mm high, 20-35mm wide green-violet
Growth Habits: Solitary, dull green stem, 1.2 inches tall (3 cm), 1.6 inches in diameter (4 cm), barely showing above the ground; apex with short white hair; each tubercle tipped by numerous white pectinate spines, 1.2 mm long.
Stem: Solitary, globular depressed, 20-30mm high, 20-35mm wide green-violet.
Root- Taproot.
Blooming Habits Mid Spring, Bloom Color: Pale Pink, White/Near White
Sun Exposure: Full Sun, Sun to Partial Shade, Light Shade
Cultivation: This is a fairly easy species to cultivate. It needs a very well-drained soil. Strong sun to part sun is required, in order to develop good spinal growth. Watering should be rather infrequent, to keep the plant compact and not become excessively elongated and unnatural in appearance. Keep dry in winter or when night temperatures remain below 10° C, it is hardy to -4°C for a short period. Assure good ventilation.
Soil pH requirements: 6.1 to 6.5 (mildly acidic), 6.6 to 7.5 (neutral) 7.6 to 7.8 (mildly alkaline)
Propagation Methods: From seed; direct sow after last frost
Other Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not over water
Suitable for growing in containers
By grafting

Turbinicarpus lophophoroides

Description: Solitary, flattened globose cactus, greyish-green or bluish-green stem, up to 1.5 inch tall (4 cm), 2 inches in diameter (5 cm); tubercles organized in 12 spirals; small woolly tubercles with 3 to 5 spreading spines.
Root: Thick and delicate.
Stem: Grayish-green or bluish-green stem that doesn’t exceed the diameter of (3) 4.5-5 (10 cm) by 4.5 high. 
Areolas: Very pronounced, woolly, later naked. With the age, the areoles become woollier and can get to completely transform the aspect of the plant.
Flowers: The flowers are white with a pinkish tinge, 1.5 inches in diameter (3.5 cm). Usually rather large and white with a pinkish tinge, 3.5-5 cm in diameter.  They are developed from the new very woolly areoles in the apex of the plant. It has scarcely irritable stamens, straight but thin, with a low insertion of the primary filaments, while in all the other species, (including the Gymnocactus and Viereckii Series) the insertion is high and the stamens are very irritable. This indicates that this species has some primitive characters. Anthers yellow/orange. Stigmas white
Sun Exposure: Light shade to part sun
Cultivation: It’s a plant adapted to a specific type of soil and quite prone to rot especially after the first flowering. A 10 -30% of natural gypsum could be added to a very well drained soil. Watering should be rather infrequent, but abundant, so that the soil becomes completely soaked. Careful watering away from the body of the plant will allow the areoles to keep their wool. The fact that the plant retracts into the soil and assume a grey-green colouring between watering, is perfectly natural and doesn’t cause any damage. Keep dry in winter or when night temperatures remain below 10° C, it is hardy to -4°C for a short period.  Assure a good ventilation. Exposures: Full sun where it obtains a natural-looking flat, or part sun.
 Min Temperature: 55°F (12°C)
Frost Tolerance: Hardy to 25°F (-4°C) for a short period
Propagation Methods: Seeds, which has good powers of germination, or from shoots which are grafted.