Orbea semitubiflora

Scientific Name

Orbea semitubiflora (L.E.Newton) Bruyns

Synonym(s)

Angolluma semitubiflora, Ceropegia semitubiflora, Pachycymbium semitubiflorum

Scientific Classification

Family: Apocynaceae
Subfamily: Asclepiadoideae
Tribe: Ceropegieae
Subtribe: Stapeliinae
Genus: Orbea

Description

Orbea semitubiflora is a beautiful succulent that forms a cluster of grayish-green stems with unique purple markings. The stems are erect, spreading, or recumbent. They are 4-angled to rounded, up to 3.6 inches (9 cm) long, with prominent conical to subulate, up to 0.6 inches (1.5 cm) long tubercles. Flowers are 5-pointed stars, up to 0.5 inches (1.3 cm) across, with dark red-wine lobes and a yellowish corona. They appear from summer to fall at the ends of the branches.

Hardiness

USDA hardiness zones 10a to 11b: from 30 °F (−1.1 °C) to 50 °F (+10 °C).

How to Grow and Care

Several species are fairly easy to grow. Others, often those with slightly hairy stems and the more unusual flowers, are more challenging and require careful watering (with some fertilizer) during the growing season and complete withdrawal of water during the winter months. A minimum winter temperature of 50 °F (10 °C) is acceptable, providing that plants are kept dry. A heated growing bench or incubator may help delicate plants to get through the colder months. However, many species live under shrubs in their habitat and prefer light shade rather than full sun.

A gritty compost is essential, and clay pots are advisable for the more delicate species. Some growers prefer mineral-only compost to minimize the chance of a fungal attack on the roots. A layer of grit on the surface of the compost prevents moisture from accumulating around the base of the stems.

Keeping Stapelias and their roots free of pests such as mealybugs is the real key to success, as fungal attacks often result from damage to stems by an insect.

Learn more at How to Grow and Care for Stapelia.

Origin

This species is native to Tanzania (Arusha Province).

Photo Gallery

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