Cyphostemma uter var. macropus (Angola)

Origin

Cyphostemma uter var. macropus (Exell & Mendonça) Desc. is endemic to a small area of southwestern Angola, with the type locality in the dry escarpment zone between Moçâmedes and Lubango (Africa). The variety was originally described as a distinct species by Exell and Mendonça from material collected on inland rocky hills, and was later reduced to varietal rank under Cyphostemma uter by Bernard Descoings. Field-collected mature specimens with a sizeable caudex are uncommon in trade, and most cultivated plants derive from Angolan seed lines.

Habitat

In its natural environment, this variety is a specialist of the dry, summer-rainfall Angolan escarpment, where it grows in shallow pockets of gritty mineral soil on quartzite and granite outcrops at altitudes around 800–1500 meters above sea level. Rainfall arrives in a single warm wet season followed by a long cool dry winter, and the air stays relatively dry for most of the year. Above ground the leafy annual shoots retreat to the caudex through the dry months, with the plant leafing out again at the start of each rains.

Description

Cyphostemma uter var. macropus is a deciduous caudiciform grape relative whose substantial, smooth-skinned caudex and soft, fleshy new growth make it one of the more sculptural Angolan taxa in serious caudex collections.

Caudex & Stem: The caudex is a thick, irregularly lobed, pale-tan to greyish storage organ that can reach 20–30 cm across in mature plants; from its crown rise annual, semi-succulent herbaceous stems that branch sparingly and die back in winter.

Roots: A coarse, woody taproot descends from the base of the caudex into the rocky subsoil, with finer laterals that exploit the brief summer rains.

Leaves: Leaves are produced in summer rosettes at the stem tips, trifoliolate to palmately compound with fleshy, softly hairy, blue-green leaflets. They drop entirely in winter dormancy.

Flowers & Fruit: In summer it bears small, inconspicuous greenish flowers in loose terminal clusters, followed by small grape-like berries typical of the genus.

Cultivation: Grow in a deep, sharply drained, mineral-rich mix with the caudex raised for display. Water generously in the warm growing months and withhold water almost completely in winter dormancy, with bright light and warm temperatures. The plant is frost-tender and resents disturbance of its taproot.