The genus Matucana contains about 15 species of globular cacti that originate from Peru. They are popular with cactus enthusiasts because they grow well in cultivation and readily produce their attractive flowers from a young age. I will focus on one species in particular, Matucana madisoniorum, perhaps the most remarkable and distinctive member of the genus, although all species are recommended and worth growing.
Matucana madisoniorum was discovered in 1957 by American botanist Paul Hutchison and described by him in 1963 to commemorate Mr and Mrs Madison who financially supported the expedition during which the plant was found. Matucana madisoniorum grows on steep slopes in canyons of the lower Río Marañón in the transitional zone between the Andes and the tropical lowland jungle. It has quite a restricted distribution and plants are fairly rare there now, but fortunately the species is easily grown from seed and is readily available in cultivation.
Matucana madisoniorum starts life as a solitary globular cactus but with age will grow slightly columnar and sometimes will offset, although my own seed-grown plants, now about 20 years old, have never done so. The most distinctive character of the plant is the epidermis or skin. It has a unique texture quite unlike any other cactus, rough to the touch and matt green colour. There are some clones that are almost devoid of spination but others have quite long spines. However these are quite fragile and can very easily be detached from the plant. Special care should be taken when handling the plant or during repotting to avoid knocking off the spine clusters.
Plants can flower when they reach about 5cm across. The blooms emerge from near the growing point and are spectacular, about 8-10cm long, orange-red with a long thin tube and petals that open to 4-5cm wide. The flower is almost rotund in shape and is most likely pollinated by hummingbirds in habitat. If you have more than one clone it is possible to pollinate the flowers. Fruits form very quickly and within a month or so reach maturity and split open to reveal the seeds inside a dry chamber. There is also a pure white flower form in cultivation which is occasionally offered for sale and well worth growing.
Matucana madisoniorum is not difficult to grow and can be treated like most other cacti but with one notable difference. Due to its low altitude habitat (about 400m) on the edge of the Amazonian jungle is does not like cold. During winter I try to keep my plants above 10ºC and even a little higher is better if you can manage to do so. At lower temperatures you may lose the plant or unsightly brown marks can appear on the body.