There are no better carpetters than the dwarf sedums, or stone crops. S. glaucum has blue-grey foliage, and spreads rapidly; S. lydium is the variety most in use, and can be had very cheaply. The tall, old variety, sedum spectabile, has been improved upon, and the novelty is called S. s. rosea. Another novelty is shortia galacifolia; it is a native of North America, and has white, bell-shaped flowers supported on elegant, hairy stems, the leaves are heart shaped, and turn almost scarlet in autumn; thus, the plant has two seasons of beauty, as it blooms in the spring. A peaty soil, with a little sand added, suits it well, if the drainage is good; and it likes a half-shady position.
Plants that are sadly neglected are the airy-fairy Sea-lavenders or Statices, with their filmy heads like purple foam; S. gmelini and S. limonium are two of the best. When cut, they last a long time, and are very useful for giving a graceful appearance to stiff bouquets.
The dwarf thalictrums are good rockery plants; they are grown for their foliage, which bears a striking resemblance to the maidenhair fern. T. adiantifolium and T. minus are very pretty; their flower-heads should always be cut off, so as to promote the production of their fine fronds, which have the property of lasting well when cut.
The aromatic scent of thyme is very pleasant on a rockery; not only should the silver and golden varieties be grown, but also those bright kinds which give us sheets of purple, pink, and white blossom during summer; to thrive they must be exposed to full sunshine, when they will attract innumerable bees. The new kind, T. serpyllum roseus, is splendid, the tiny flowers coming in such profusion as to completely hide the foliage. All are low-growing, having the cushion habit of growth.
Veronicas are not often seen, yet they are exceedingly pretty, and continuous bloomers. Amateurs should not begin with the shrub tribe, as these are somewhat tender, but if V. incana, V. longifolia-subsessilis, and V. prostrata are obtained, they will be sure to please. The first and last are low-growing, but the other is two feet high, and has long racenes like soft blue tassels, which hang down in the most charming way.
A few words on some more bulbs that look well on rockeries, besides the crocus and dwarf iris before-mentioned, may not be amiss: the winter aconites are most appropriate so placed, and show to greater advantage than in the level border. Their golden flowers, each surrounded by a frill of green, come forth as early as January, if the weather be propitious.
The chionodoxa, called also glory of the snow, is very fresh and pretty, with its bright blue flowers having a conspicuous white eye. If left undisturbed they will spread rapidly, and come up year after year without any further trouble; they are very cheap, and will do in any soil.
Snowdrops are charming on rock-work, and may be placed close to the chionodoxa, as they bloom almost together.
The grape-hyacinths have very quaint little flowers of a bright dark-blue colour, on stalks about five or six inches high; they flower for some weeks, and must be massed together to get a good effect.
The early-flowering scillas resemble the chionodoxas, but last much longer in bloom. They are very easy to manage, and rarely fail to make a good show. S. siberica is the best-known variety, and can be obtained very cheaply.