This rampant grower can still be seen in rockeries all over the country, spreading like a weed and choking out other plants. The silvery-leaved sheets bearing whitein early summer are out of place in the average-sized rock garden, but the ordinary varieties are useful for covering large dry banks.
VARIETIES: You will find Snow-in-summer listed in catalogues or offered for sale at the garden centre under the latin name C. tomentosum. Its basic details are height 6 in., spread 2 ft or more,
Flowering period: May-July. The whiteare about 0.5 in. across. C. biebersteinii is a very similar species but the are larger and woollier. lanatum because it is much less invasive than the others, but it needs protection from winter rain and is not worth the trouble.
SITE AND SOIL: Any well-drained soil – thrives best in full sun.
PROPAGATION: Sowor divide clumps in spring.