Scientific Name
Haworthia retusa (L.) Duval
Common Name(s)
Star Cactus, Window Succulent
Synonym(s)
Aloe retusa, Apicra retusa, Catevala retusa, Haworthia retusa var. retusa
Scientific Classification
Family: Asphodelaceae
Subfamily: Asphodeloideae
Tribe: Aloeae
Genus: Haworthia
Etymology
The specific epithet "retusa (re-TOO-suh)" means "blunt, dull; retuse" and refers to the "retused" leaf shape (curved back like a thumb).
Origin
Haworthia retusa is native to South Africa (a small area around Riversdale in the Western Cape Province).
Description
Haworthia retusa is a small succulent that forms star-shaped rosettes of thick, fleshy, lime green leaves with a triangular, translucent end area marked with longitudinal lines. It usually grows as a solitary rosette in the wild but can offset and even form a clump of rosettes in cultivation. The rosettes can reach up to 6 inches (15 cm) in diameter. The leaves are deltoid and recurved, measuring up to 3.2 inches (8 cm) long and 0.8 inches (2 cm) wide.
The flowers are small, tubular, white with greenish-brown veins, and appear on unbranched stalks that can grow up to 20 inches (50 cm) long in late spring to summer.
How to Grow and Care for Haworthia retusa
Light: Although some species can grow in full sun, most Haworthias are adapted to thrive in partial shade. Place the potted H. retusa in a bright area with some protection from the hottest rays of the day.
Soil: All Haworthias do not like their roots to remain wet for prolonged periods, so their potting soil should be well-drained. Use a commercial succulent potting mix, or make your own.
Hardiness: Haworthias like warmer temperatures in the summer but cool in the winter. However, they do not like being too cold. H. retusa can withstand temperatures as low as 30 to 50 °F (-1.1 to 10 °C), USDA hardiness zones 10a to 11b.
Watering: In spring and fall, when the growth is most active, water Haworthias thoroughly, then wait until the top of the soil dries out before watering again. Water your plants less during the winter when their growth slows down significantly. During the hottest summer months, when Haworthias are mostly dormant, water it just enough to keep the leaves from shriveling.
Fertilizing: Haworthias do not require much fertilizer, but fertilization is a good idea for optimum growth. Feed only with a dilute fertilizer and only during the active growing season.
Repotting: These succulents are generally slow-growing and can stay in the same pot for years. However, for best health, H. retusa should be repotted into fresh soil every two to three years.
Propagation: Vegetative propagation, especially by offsets, is the quickest and most common method of propagating Haworthias. They can also be propagated by leaves and seeds. Remove the offsets when they have started developing their own roots. Sow seeds in spring or fall in a well-draining soil mix.
Learn more at How to Grow and Care for Haworthia.
Toxicity of Haworthia retusa
Haworthia species are generally non-toxic to humans and animals.
Varieties, Cultivars and Hybrids of Haworthia retusa
Links
- Back to genus Haworthia
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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