Ageratum houstonianum

A frost-tender herbaceous annual to 1/2-1' tall, mounding with clusters of fluffy, aster-like flowers that should be planted with 10-12 inches of space.  Genus name comes from the Greek "a" meaning not and "geras" meaning old age because the flowers hold their color for a long time. 

Forms clumping mounds with colors of pink, white & blue from May through October. Dependable flowering annual. Confused with ageratums that are perennials with tall, erect stems and leaves well-spaced out, but similar in appearance with leaves and flowers. 

This plant is moderately drought tolerance but prefers rich, moist, well-drained soil as well as full sun. It is good for beds and containers, blooming from spring to frost.  Taller varieties make good cut flowers. This plant is seldom damaged by rabbits and deer. Used for edging or low massing plant in bed. Relative pest/disease free

Insect Pests, Diseases, and Other Plant Problems: susceptible to powdery mildew. Some cultivars have shown excellent resistance to phytophthora. See Phytophthora Root and Crown Rot in the Landscape.

Family name Asteraceae (Compositae)

Quick ID Hints:

• Mounded herb as wide as tall, often 6"
• Terminal cluster of small heads
• Flowers all tubular, tassel-like