HOUSELEEK

Native to mountains of Europe. Form tightly packed rosettes of fleshy, evergreen leaves; spread by little offsets that cluster around parent rosette. Clustered, star-shaped summer flowers in white, yellowish, pink, red, or greenish; pretty in detail but not showy. Blooming rosettes die after setting seed, but offsets (easily detached and replanted) carry on. There are many species; all are good in rock gardens, pots, even in pockets in boulders or pieces of porous rock. Need excellent drainage. Water only to prevent shriveling.

cobweb houseleek

sempervivum arachnoideum

• Gray-green rosettes of many leaves are joined by fine hairs for a cobweb-covered look.
• Larger rosettes (to 2 inches wide) are surrounded by a host of smaller ones.
• Spreads slowly to make a dense mat to 1 feet or wider.
• Bright red flowers on 4- to 6 inches stems.
• Cebennense has cobwebby green leaves with burgundy tips.
• Leaves of 'Rubrum' are flushed with red in spring.

sempervivum hybrids

• Most selections sold fall into this category.
• All form crowded rosettes that vary mainly in color and leaf shape.
• Oddity is the most widely sold, with burgundy-tipped green tubular leaves; grows 8 inches high, 12 inches wide.
• Black has deep maroon leaves with contrasting green new growth.
• Carmen has large rosettes of green leaves tipped in red.
• Leaves of 'Krebs' are chocolatey green; those of 'Rubikon Improved' are red.

hen and chickens

sempervivum tectorum

• Gray-green, 2- to 5 inches-wide rosettes spread quickly to form clumps to 2 feet or wider.
• Leaves have red-brown, bristly tips.
• Red or reddish blossoms are borne on stems to 2 feet tall.
• An old-time passalong plant.