Mexican Little Sun Cactus/Mammiilaria microhelia
Mostare globular, but this one makes narrow, cylindrical stems. Mammillaria are deservedly the most popular group of , as almost all flower readily and are easy to grow.
Mammillaria microhelia is a small-growing species, although in time the stems will elongate to more than 30cm (1ft) in length and creep across the ground. As a young plant, it tends to remain solitary, but later offsets from the base to make a clump. It is densely covered in short golden spines, which make it almost impossible to see the plant’s body. Sometimes it produces a longer central spine from each areole, which can be yellow, brown or black. The small flowers appear in April-May.
Mammillaria microhelia is quite tolerant of temperatures down to 5°C (40°F) if kept fairly dry. Like most plants, it will benefit from good ventilation, but not draughts.
This plant requires a bright situation at all times and will grow well in a South-facing window.
Water well during the Summer, allowing theto dry before watering again. In the Autumn and Winter, keep the plant fairly dry, giving only enough water to prevent shrivelling. ‘Mammillaria microhelia’ comes from very arid areas and will benefit from a dry atmosphere.
Feed every 1-2 weeks. During the Spring and Summer with afood, or one recommended for tomatoes at about half strength.
This cactus will do best in a well-drained compost containing about one third grit. Repot at least every two years.
The stems of very old and neglected plants can become dirty and discoloured. Normally the plants will make new offsets from the base, so it is a good idea to remove the old stems and let the new ones develop. During the Spring or early Summer, cut the old stems back to 5-8cm (2-3in).
Cut the top 8cm (3in) from the removed stem and discard the base. Allow the cutting to dry for 1-2 weeks until the base has formed a hard callus. Half fill a small pot with compost, then add a layer of gravel to cover the compost. Stand the cutting on the gravel and fill the pot with more gravel. Place the pot in a bright, warm position and keep the compost slightly damp. The cutting should root within 3-6 weeks. The following Spring it should be potted as normal.
Rot: Although not prone to pests or diseases, this cactus will soon rot if kept wet at low temperatures. Water sparingly in Winter and surround the plant’s neck with gravel so that it does not become sodden.