Rebutia (Crown Cactus) is a genus of mostly clump-forming, spherical to columnar cacti in the family Cactaceae. It is native to Bolivia and Argentina where they are grown mostly at altitudes of around 3500 m. The genus name Rebutia is named after a French cactus nurseryman, Pierre Rebut (1828-1898).
Rebutia species are small and easily grown cactus, cultivated for their brightly colored flowers which come in shades of red, yellow, orange and violet. The much-ribbed, tuberculate green stems have short spines. Shoots appears at the base of the cactus body, as do the flowers. The flowers are produced in profusion from plant bases, usually 2-3 years after raising from seed. Most of Rebutia species are intolerant of the cold and require daytime temperature of 20°C to 30°C during summer months. They require a sunny position or partial shade and well-drained soil. Propagation is by seed or replanting the new shoots. Pests are red spider mite and mealy bugs.
Rebutia arenacea is a spherical cactus which can grow up to 5 cm high and 6 cm broad. It has a brown-green stem with white spines on spirally arranged tubercles. In spring, it produces golden yellow flowers, 3 cm in diameter.
Rebutia aureiflora, 10 cm tall and 20 cm wide, is a clump-forming cactus with a dark green stem, which is often tinged with violet-red. It has stiff radial spines and longer, soft central spines. This cactus bears masses of yellow, violet, or red flowers in late spring.
Rebutia fiebrigii, 10 cm tall and 15 cm wide, is a clump-forming cactus. It has a dark green stem which is densely covered with soft white spines of 0.5 cm long. It bears bright orange flowers, 2-3 cm in diameter, in late spring.
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Otakar Šída
