These now include what we have so long known as the echeveria and sem-pervivum. They are dwarf succulents, a few of them forming stems, mostly perennials. Very few are of any value as flowering plants. Many of them are indispensable for carpet bedding. In fact, the rage for carpet bedding of twenty-five years ago brought several species of the echeveria into great prominence and millions were grown. They will always be most interesting plants for the rockery.
They are of the easiest culture, all the useful species sending out a number of offsets, which can be removed from the parent plant in fall and planted into sandy loam thickly in flats. The species such as metallica and retusa that form stems should not be exposed to frost, and will do very well in a night temperature of 50 degrees. But for wintering most of them a much lower temperature will do; and give them little water during the dark months.
While propagation by offsets is much the easiest plan, they can all be raised from seed, which is best sown in very early spring. The following list includes the most useful as well as handsome species:
C. sempervivum, house leek; perfectly hardy.
C. gibbiflora metallica, fine for center of carpet beds, or worthy of pot culture; broad, thick leaves of a metallic hue.
C. agavoides, beautiful form, resembling an agave, with sharp points to the leaves; one of the handsomest.
C. Californica, fine form; good for carpet bedding.
C. glauca, leaves form a dense rosette; largely used.
C. secunda glauca, this is the one most in use; does well in any soil, is easily and rapidly propagated, and for carpet bedding is unequaled; there are several varieties, all useful.
Some recent experience with this variety so largely used is worth recording. Our park department, having many thousands on hand and being short of room, put the flats into coldframes that had been excavated two feet below the surface. With the use of mats the plants kept in excellent condition the entire winter, and were not watered once from November to April, but frequently must have been frozen. If kept very cool or exposed to frost, the soil must be dry and at all times avoid drip. No doubt most of the echeveria section will endure a severe freezing.
C. Peacockii, is perhaps the most ornamental of all, and much less common than most others.
C. Ruthenicum, good for rockery; quite hardy.
C. Verlottii, a pretty species, and hardy.
C. rosea, a fine form; suitable for large designs in carpet bedding.
C. retusa, is the only one we ever have grown as a flowering plant for fall and winter sales. It sends up several flowering stems thickly covered with very pretty flowers. Being a succulent, it is a most satisfactory house plant, and twenty years ago we grew it largely. It is well worth growing. Plants that have flowered should be cut down within a few inches of the ground and from the stem you will get several cuttings, which will root quickly in the sand and can be potted, and when there is no longer danger of frost, planted out of doors a foot apart in good rich earth. You want these plants to grow, unlike those you have crowded into the carpet beds. They will grow fast, and if inclined to flower too early, pinch out the flowering stem till September. They lift, of course, with the greatest ease. We like to put them into a 5-inch pot. For inside arrangements of plants, such as are often seen in the dining-rooms of hotels, this plant is of especial value, and the species metallica would also be for its grand leaves. A cold dampness is all that will hurt them.
Some of the species do not make offshoots, or not in quantity enough to propagate sufficiently fast. The leaves can be pulled off when perfectly mature and very slightly inserted in sand and kept dry; on the ends or base of the leaf small plants will form, which when of sufficient size can be potted and started growing.
You frequently see the bedding species used on the margins of beds where the edge of the bed is nearly perpendicular. Ordinary soil would wash down at the first rain. For these positions a mixture of clay and cow manure is used, and the plants put in when it is moist.