Spring-flowering bulbs with flower spikes like miniature. They succeed on any reasonably fertile soil and should be planted 2—3 in. deep in early autumn. Some are pleasantly fragrant. The best known is probably Heavenly Blue ( armeniacum) which bears gentian-blue in April. It grows to 8 in. and is delightful for . There are several other kinds which deserve to be grown more widely. M. botryoides caeruleum has dark blue . The white form of this species has a honey-like fragrance. The species catalogued as M. tubergenianum Cantab or the Oxford and Cambridge is usually two shades of blue. M. plumosum (feather or plume ) is late, being usually in bloom in May. It is very distinctive, with plume-like heads of mauve flowers. All these grow to about 8 in. and should be left undisturbed until the clumps show signs of overcrowding when they can be lifted and divided in late summer.