
SCIENTIFIC NAME: Ageratum houstonianum
COMMON NAME: Mexican ageratum, flossflower
FAMILY: Asteraceae (Compositae)
TYPE: annual
LEAVES: alternate, ovate to triangular, up to 4" long, crenate margin
FLOWER: heads to 1/4" across in cymose clusters; excellent blue shades, lavender, pink, or white; no ray flowers
SEASON OF BLOOM: spring to fall, declines during heat of summer
GROWTH HABIT: 6" to 24", most often mound-like habit
SOIL: moist, well drained
SUN: full sun with afternoon shade (best for zone 7b)
UTILIZATION: edging or border, tall cultivars for cut flowers or background; containers
DISEASES: root rot, powdery mildew in poor air circulation areas
INSECTS AND RELATED PESTS: none serious
PROPAGATION: seed, stem cuttings
MAINTENANCE: cut back in summer to promote fall flowering
NOTES: Blue Hawaii is a good performer
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