Opuntia pycnacantha

Opuntia pycnacantha is a strikingly handsome opuntia; its light spination is in contrast with red-brown areoles and the fresh green colour of the epidermis. It is a slow grower but less tolerant than the above-mentioned species. It requires careful watering and suffers if the compost is not well drained. It comes from the Baja California Peninsula. Of many other opuntia species, it is worth mentioning the species native to cooler regions of the United States and Canada. These are remarkably frost-resistant and can be grown in Europe on rocks, terraces and balconies. In June, they are a mass of yellow blossoms. The most famous ones are O. phaeacantha, O.fragilis and O. compressa. They serve as reliable stocks for the delicate scions of Pediocatus spp. and Sclerocactus spp. for growing outdoors.

Opuntia microdasys

Many succulent growers started their collections with this rewarding, indestructible plant. In the wild, this cactus grows into small shrubs composed of flat segments, but there are many forms differing in size and shape of segments and in the colouration of the glochid cushions. The glochids are yellow , red, brown, white. The cultivar ' Albatus' , sometimes called 'Angel's Wings', can be particularly recommended to growers, its glochids unlike those of other forms being not prickly. As with most opuntias, O.microdasys can easily be propagated from detached segments, which root readily and rapidlly grow new segments after planting. The flowers are of course a desirable ornament, but they usually appear on larger plants and are a rare phenomenon in amateur collections.

Parodia leninghausii

Goldfinger, golden ball cactus
In the wild, the sloping crown of this cactus faces the sun. Its short, thick, columner stem is slightly curved at the base and is covered in long, soft, golden spines. Clusters of large, buttercup-yellow, open-faced flowers are produced on the plant crown in summer. The cactus offsets freely when it is about 5 - 10 years old.
H and S 90 cm (3 ft). Min. 7°C (45°F).

Parodia otaviana

The long, hooked, golden or rust-brown spines of this small cactus sontrast dramarically with its scarlet blooms. These are freely produced in spring and summer once the plant body has reached 5 - 8 cm (2 - 3 in) in diameter. Tiny papery fruits follow. Slow-growing, the globular green body eventually becomes slightly columnar in shape. This sun-loving plant is one of the easiest Parodia species to grow.
H 20 cm (8 in), S 18 cm (7 in). Min. 7°C (45°F).

Rebutia krainziana

Is a 5 cm high plant, usually growing singly, with prominent white areoles and brilliant red flowers. Orange and yellow-flowered forms also exist. R. minuscula with an inconspicuous atem but frequent and abudant flowers is the best-known species.

Rebutia senilis

Rebutia senilis differs from the other species in its thick, white spines each up to 3 cm long. There are varieties with red, orange and yellow flowers. Like most species of the genus Rebutia they are autogamous, that is the fruits and seeds are the resultsof self-pollination though in a collection hybridization is common. Cultivation of rebutias is easy: they need plenty of sunshine, water and fresh air in summer, and a porous compost. In the resting period, they require an absolutely dry environment and temperatures around 10°C. Only some of the recently imported species from lower situations in Bolivia prefer warmer winters.