Scabiosa Caucasica.—On any but very cold soils this is a true perennial. The flowers are abundantly produced on long stalks, and are useful for cutting.
Polemonium Cæruleum.—Jacob’s Ladder. An old-fashioned plant, worthy of inclusion in modern gardens. It blooms from early June to September.
Catanache Cærulea.—Blue Cupidone. An easily grown, free flowering plant. The colour is especially pleasing.
Centaurea.—Knapweed. One of the best of this family is C. montana, a variety with cottony leaves, and a profusion of flowers not unlike the blue Cornflower.
Iris Pallida.—Great Purple Flag. The stately, swordlike leaves rising in sheaves amid the border plants are most welcome, and the rich velvety colouring of the quaint flowers must appeal to all. The variety Mandraliscæ should also be grown.
The following are dwarf growing subjects:—
Veronica.—Speedwell. Among the varieties having flowers of a true blue shade are dentata and incana, the latter with pretty silvery foliage. V. prostrata is a free bloomer of dwarf, spreading habit.
Gentiana Acaulis.—Gentianella. One of the most beautiful blue flowers we have.
Statice.—Sea Lavender. The small flowers borne on wiry stems may be cut and used for winter decoration. S. latifolia is the finest of the genus.
Ajuga Osnafera.—Bugle. These plants bear close spikes of small flowers, and the effect, when boldly grouped, is decidedly pleasing.