Scientific Name: Ageratum houstonianum
Common Name: floss flower
Family Name: Asteraceae
Origin: Central America, Mexico
Hardiness Zone: Zone 8b: (-9.4 to -7 °C)
Plant Type: Annual, Flowering cut plant
Mature Size: 0.2 - 0.4m x 0.1 - 0.3m (height x width)
Habit: Spreading, Upright
Form: Vase
Texture: Medium - fine
Landscape Uses: Bedding plant, Container planting, Rock garden
Exposure: Full sun only if soil kept moist, Part sun/part shade
Soil or Media: Well-drained
Leaves: Simple, Opposite, Soft flexible, Pinnate venation, Pubescent, Ovate, Ciliate, Crenate, Dentate, Serrate
Flowers: Head (capitulum), White, Blue, Violet, Purple, Pink, Jul-Aug-Sep-Oct
Fruit: Cypsela (achene + calyx), Brown, Oct-Nov
Key ID Features:
Habit bushy, cultivars 20 to 1m tall; leaves simple, ovate 3-5cm long x 2-4cm wide; flower heads 4-7(-15)mm wide, 6-15(-70) in a cymose-corymb-like arrangement, fluffyness due to long branched style branches, violet to blue, pink to purple, or white, Jul-Oct.