194 ROCK GARDENING FOR AMATEURS 



Thrift-like spiny foliage, and bearing small heads of 

 rose-coloured or white blossoms in May on stalks about 

 three or four inches high ; it belongs to the same family 

 as Thrift and Sea Lavender (Plumbaginaceae) . This plant 

 dislikes disturbance, and needs to be firmly planted in 

 light, well-drained soil, in a sunny position. In wet 

 ground it is rarely satisfactory. Acantholimon glumaceum 

 is the one most generally grown, though there are two 

 others worthy of mention namely : A. Kotschyi, having 

 white blooms ; and A. venustum, pink. Propagation 

 is not easy, though a certain proportion of cuttings will 

 form roots if taken after the flowers are over and inserted 

 in sandy soil beneath a shaded bell-glass. 



Achillea (Milfoil or Yarrow). The Yarrows are re- 

 presented among our own wild flowers by the common 

 kind of the fields with pink- white blooms (A. Millefolium), 

 and by the bolder Sneezewort (A. [Ptarmica). They 

 are a race of plants characterised by silvery grey foliage 

 and flattish bunches of white or yellow flowers. They 

 belong to the great Daisy family (Compositae) , and the 

 dwarf kinds are native of the European Alps. Only 

 a few are of sufficiently compact growth for the rock 

 garden, and even these are liable to become weedy 

 unless planted in poor, stony, sandy soil and a sunny 

 position. They are all the better for a covering of 

 glass during winter; in the absence of this the leaves 

 are liable to decay. A little limestone mixed among 

 the soil has the effect of brightening the tone of the 

 grey leaves. The best method of propagation is by 



