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Alyssum spinosum L.

Modern name

Ptilotrichum spinosum (L.) Boiss.

Synonyms

Ptilotrichum spinosum (L.) Boiss.

A spiny shrub of dense habit, with interlacing branches, 6 to 15 in. high, usually much more in diameter; young shoots covered with a close, silvery scurf; spines slender, 18 to 58 in. long. Leaves narrowly oblong to oblanceolate, tapered at the base, pointed or rounded at the apex, entire; 12 to 2 in. long, 116 in. or less wide; covered on both sides with silvery, star-like down. Flowers white or pale rose, fragrant, 310 in. wide, numerous and closely packed in terminal umbellate racemes 34 in. wide; petals four, obovate, tapered to the base. Pod circular to obovate, 18 in. wide, glabrous, terminated by the persistent style.

Native of S.W. Europe and N. Africa, common in calcareous rocky places in S. France and Spain; introduced in 1683. It succeeds very well in full sunshine in rock gardens south of London, flowering in May and June.


Genus

Alyssum

Other species in the genus

[No species article available]