HARDINESS: Zones 4 to 8
PREFERRED SOIL pH: Neutral to slightly acid
PREFERRED SOIL TYPE: Average
PREFERRED LIGHT: Sun to partial shade
ATTRIBUTES: Low-growing green or bronze foliage rosettes; for edging, pots, beds
SEASON OF INTEREST: Evergreen foliage has year-round appeal
FAVORITES: S. tectorum, S. arachnoideum, S. octopodes
QUIRKS: Leaves resist fire; some species were once grown on roofs to retard fire
GOOD NEIGHBORS: Mugo pine, sedums, sun rose
WHERE IT GROWS BEST: In sun to partial shade and gritty soil
POTENTIAL PROBLEMS: Excessive moisture and shade can cause rot
RENEWING PLANTS: Lives years; remove damaged plants and flowering stems as needed
CRITTER RESISTANCE: Good
SOURCE: Plant offsets
DIMENSIONS: Less than 4 in (10.2 cm) tall; clumps spread to 12 in (30.5 cm) wide
Hens and Chicks in the Landscape
It's hard to resist the succulent, fleshy rosettes of hens and chicks, properly known as sempervivums, which manage to be tough and cute at the same time. Their long lives and dependability are reflected in their botanical name, which translates as "live forever." They are called hens and chicks because the round offshoots on short stems crowd around the mother plant like chicks around a hen.
These sun-resistant plants form wonderful patches of texture and foliage color in rocky or dry, parched places. They can take a beating, with very little water or even soil, for they originated in the rugged mountains of Europe and the Middle East. They do well on slopes, in rock gardens, and in other sites that offer excellent drainage. With a little encouragement, the clumps will carpet wide swaths, filling every nook and cranny with their many "chicks."
Hens and chicks are also suitable for low, broad containers where they can be viewed from above. Where winters are too cold to grow sempervivums outdoors, containers can be kept through the coldest months in a cool garage or enclosed porch.
Sempervivum foliage is usually light or dark green, but may also be brownish or reddish, either at the fleshy leaf tips or throughout the whole plant. The star-shaped flowers are usually pink or white. Oddly, most types look much better when they are not flowering because the flowers, which shoot upward on spindly stems, detract from the neat, ground-hugging habit of the plants.
Commonly called houseleek, Sempervivum tectorum is a popular, easy-to-grow species, with big green or bronzy pointed rosettes that need almost no care and increase quickly. This and several other old favorites are often shared among gardeners because of their prolific habits and willingness to be transplanted. Of special interest are spiderweb houseleeks, S. arachnoideum, with white hairs covering the reddish rosettes in a "spiderweb." The species S. octopodes has long, chick-bearing stems, creating an unusual effect.
Growing Hens and Chicks
Set plants in a site with full sun and sandy, well-drained soil. In heavy clay soils, plant them on slopes to maximize drainage. The only time hens and chicks need extra moisture is when new plants are set out. Keep them barely moist for a few weeks, then they can fend for themselves.
After a rosette matures and flowers, it dies, so simply remove it and fill the space with a younger offset. When removing a chick from its mother, take at least a 1 in (2.5 cm) long stem along with it. Bury the stem stub under 1 in (2.5 cm) of gritty soil, and use pebbles to hold it in place until the chick develops roots and can hold its own. While virtually pest and disease free, hens and chicks can succumb to root rot if they are exposed to waterlogged soil, particularly in hot, humid climates.