Scientific Name:
Ageratum houstonianum
Pronunciation:
uh-JUR-uh-tum hew-stone-ee-AY-tum
Common Name:
floss flower
Family Name:
Asteraceae
Plant Type:
Annual, Flowering cut plant
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.
Habit:
Spreading, Upright
Form:
Vase
Texture:
Medium - fine
Mature Height:
0.2 - 0.4m
Mature Spread:
0.1 - 0.3m
Growth Rate:
Fast
Origin:
Central America, Mexico
Hardiness Rating:
Zone 8b: (-9.4 to -7 °C)
Exposure:
Full sun only if soil kept moist, Part sun/part shade
Soil/Growing Medium:
Well-drained
Landscape Uses:
Bedding plant, Container planting, Rock garden
Additional Info:
Leaf Morphology:
Form:
Simple
Arrangement:
Opposite
Texture/Venation:
Soft flexible, Pinnate venation
Surfaces:
Pubescent
Colour in Fall:
Yellow
Shapes:
Ovate
Apices:
Acute, Obtuse
Bases:
Attenuate, Cordate
Margins:
Ciliate, Crenate, Dentate, Serrate
Inflorescence Type:
Head (capitulum)
Flower Morphology:
Flowers perfect
Number Of Petals:
5
Corolla Shape:
Tubular
Ovary Position:
Inferior
Colour (petals):
White, Blue, Violet, Purple, Pink
Flower Time at Peak:
Jul, Aug, Sep, Oct
Additional Info:
Ray florets absent
Fruit Type:
Cypsela (achene + calyx)
Fruit Colour:
Brown
Fruiting Time:
Oct, Nov
Additional Info:
Fruit insignificant
Bark or Stem Colour:
Green
Pest Susceptibility:
Aphids or adelgids, Crown rot, Mildew, Mold, Root rot, Rust, Whitefly or psyllids (Deer resistant)
Course(s):
- HORT 2355
- Level 3 Apprenticeship
Location(s):
- (NCA) Not Currently Available : needed