July 10, 2007
This plant earned its survival skills the hard way its a native plant of rugged climates such as Afghanistan or the rocky Himalayas. Perovskia atriplicifolia looks like a periwinkle-blue cloud when it blooms in late summer. This shrubby perennial, which may span 4 feet, tolerates our alkaline soils and handles dry sites, which is why its a workhorse of supermarket parking lots.
Where to plant: Full sun, in really well-drained soil. Break up clay soil by mixing in some sand as well as plenty of compost. Water once a week for the first year. In early spring, prune back old, dry growth to 6 inches. Tough as nails and showy through the entire growing season, says Scott Mehaffey, design manager at Craig Bergmann Landscape Design in Wilmette (www.craigbergmann.com). Treat it as a full-sun shrub, and itll be spectacular.
Achilles heel: Cant tolerate soil that stays wet.