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Siam weed

Siam weed

Chromolaena odorata

shrub☀️ full sun💧💧 moderate waterZone 10a – Zone 12b

A fast-growing tropical shrub with aromatic foliage and clusters of small white or pale blue flowers. Highly invasive in many regions outside its native range.

Overview

Form
Spreading
Growth Rate
fast
Size
3–10′ tall × 3–10′ wide
Dormancy
evergreen

Tolerances & Soil

moderate
Zone 10aZone 12b
1471013
ColderWarmer
Zone range: Zone 10a to Zone 12b

Seasonality

Bloom Season

J
F
M
A
M
J
J
A
S
O
N
D

Season of Interest

SummerFall

Shrub

Woody multi-stem plants at eye level.

Succession Role

pioneerearly successional

Native Range

Central and South America

Function & Care

biomass/mulchdynamic accumulatorerosion controlmedicinalwildlife benefit

Establishment & Care

Establishment
easy
Maintenance
high
Propagation
seed, cutting

Companion Planting

Plants well with