Marlothistella uniondalensis is found in South Africa, and grows in grasslands or karroid vegetation in the Western Cape province. The specific epithet uniondalensis refers to Uniondale, a small town in the Little Karoo, where the species is found.
It is a small succulent Mesemb with thick taproots and long, narrow, grey-green leaves that can grow up to 15cm tall. It forms a number of branching taproots that form a caudex-like structure, which can reach up to 8cm in diameter. The leaves grow up to 4.5cm long and are cylindrical at the base and sharply pointed at the top.
During the winter months, the plant produces stunning flowers with narrow petals ranging from white and pale pink to magenta. The fruits are 5-locular capsules.
Marlothistella uniondalensis needs bright light but not too much direct sunlight. A windowsill that receives 4–5 hours of direct sunlight in the morning and partial shade in the afternoon will be a perfect spot for indoor growing. High temperatures are not a problem as long as there is plenty of fresh air and ventilation, but this plant is not cold-hardy. It can reportedly take temperatures as low as -4°C but that is not recommended in humid conditions that a UK greenhouse might experience.
The plant thrives in porous and well-drained soil. It needs a deeper than usual pot to accommodate the tap roots. During the dormant period, usually in summer, Marlothistella uniondalensis requires little or no water. In the autumn, once it starts growing again, water thoroughly but allow the soil to dry between waterings. The plant can stay in the same pot for many years but will need a bit of feeding. If you repot this plant every two years, it does not need fertiliser. The best time to repot is at the beginning of the growing season. When it is potted up, the plant can be progressively raised over the soil level so that some of the roots can be seen and some growers do this for aesthetic effect.
Regarding propagation, although it is usually grown from seeds, Marlothistella uniondalensis can be easily propagated by division. During late summer, just before it begins to break dormancy, is the best time to divide the plant, while the autumn is the ideal time to sow the seeds.
Photos: Ed Shaw
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