Sometimes still referred to by its previous name of Sulcrorebutia steinbachii, (also Rebutia steinbachii – Ed.) this plant comes from north and east of Cochabamba in southern Bolivia and grows mainly on flat, dry, stony areas at an altitude of 2,900–3,800 metres above sea level. It is a clumping plant which readily forms new heads of up to 5cm in diameter especially in cultivation.
Fig. 1 Plant in a 50cm (20″) pot after I had help with repotting
Positive identification is not always straightforward. The spines can vary both in length and colour, and white, yellow, red, brown or black forms are available. Flowers colours are also very variable even within a single population. Yellow, orange, red, magenta or violet, often with white inner petals have been discovered.
Fig. 2 Plant showing its gratitude after repotting
It is quite tolerant of a range of conditions in cultivation but as with many rebutias, would probably appreciate the addition of some ericaceous compost in the mix to reduce the soil pH. It has shown it can tolerate temperatures down to -4°C (25°F) if kept totally dry so will not break the bank in extra heating costs.
The most challenging aspect in growing this plant (as with most in this genus) is its susceptibility to Red Spider Mite. This can be discouraged by providing good air movement around the plants and controlled by the regular spraying of a ‘smothering agent’, such as SB Plant Invigorator or Neem oil during the growing season. This process will only kill the adults, not the eggs and so it is recommended be done approximately every two weeks.
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