Description
Alyssum – Madwort
There are about 170 species from Europe, North Africa, and Southwest and Central Asia of tufted, mat, or hummock forming perennial and sub shrubs, in this genus. Mainly low spreaders with small 1/8-1” elliptical leaves. In spring and early summer they are smothered in corymb-like racemes of tiny white, cream, yellow, or pink 4 petaled, cross-shaped flowers. Most are less than 8” tall with a few of shrubbier species reaching 24” tall.
Grow in full sun with gritty moderately fertile well drained soil, ideal for growing in rock crevices and dry stone wall plants, soak in spring and summer. They’re fairly frost hardy. Trim lightly after flowering to maintain compactness.
Prone to club root, downy mildew, basal stem rot, root rot, caused by fungi may occur as well as aphids.
Alyssum spinosum – Ptilotrichum spinosum – Natural occurs in Southern France and Southeast Spain growing to a twiggy sub shrub 2’ feet tall and in breadth. It produces spiny tipped gray-green to silver foliage. It bears dense corymb like racemes of white flowers and become purple tinted as it ages.
Zones 6-9
