Plant of the Month September 2010

Androsace barbulata

Androsace barbulata early in the season (left) then later (right): note the change in the eye colour; photo by Todd Boland

Description and general information

This Androsace is relatively new in cultivation. This species is closely related to A. villosa. It was collected by Vojtec Holubec from limestone crevices in the Western Caucasus at 1,900m.

Plants form small, somewhat hairy rosettes, which are topped by clusters of white flowers whose eye turns from yellow to pinkish-red. The entire plant is less than 10 cm in height. Most authorities rate it as hardy to zone 5, but with adequate winter protection, it would probably be fine in zone 4.

Cultivation

Well-drained, scree-conditions suit this species best. It is ideal for the alpine trough, crevice garden or alpine house. In cooler climates, full sun is fine but in warmer regions, shade from the hottest afternoon sun is advised.

Bloom period

In mild climates, this species may bloom in April but in cooler, more northern regions, June is the standard month.

Propagation

Seed and rooted offsets

Seed

Seeds may be directly sown at 20 C with germination expected within 3 months.

Division

Large plants could be dug and divided after blooming.

Cuttings

Plants produce offset rosettes which can be separated and rooted in a shady frame in a mix of coarse sand with a little peat.

References

www.onrockgarden.com

rev 5.0