Chromolaena odorata is a rapidly growing perennial herb. It is a multi-stemmed shrub which grows up to 2.5 m (100 inches) tall in open areas. It has soft stems but the base of the shrub is woody. In shady areas it becomes etiolated and behaves as a creeper, growing on other vegetation. It can then become up to 10 m (33 feet) tall. The plant is hairy and
glandular and the leaves give off a pungent, aromatic odour when crushed. The leaves are opposite, triangular to elliptical with
serrated edges. Leaves are 4–10 cm long by 1–5 cm wide (up to 4 x 2 inches). Leaf
petioles are 1–4 cm long. The white to pale pink tubular flowers are in
panicles of 10 to 35 flowers that form at the ends of branches. The seeds are
achenes and are somewhat hairy. They are mostly spread by the wind, but can also cling to fur, clothes and machinery, enabling long-distance dispersal. Seed production is about 80,000 to 90,000 per plant. Seeds need light to germinate. The plant can regenerate from the roots. In favorable conditions, the plant can grow more than 3 cm per day.
Common names Common names include
acheampong leaves,
siam weed,
rouge plant,
Christmas bush,
triffid, or
jack in the box, among others according to region and language. ==Classification==