Siam Weed
Chromolaena odorata
Also listed as Eupatorium odoratum, Eupatorium conyzoides
Also known as Triffid Weed, Turpentine Weed, Kingsweed
Climate Match for your location
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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.
Why grow it
Chromolaena odorata establishes quickly in warm climates with minimal inputs, making it useful for rapid biomass production, erosion control, or pioneer plantings on degraded land. Compared to slower-growing native alternatives, it reaches harvestable size within one to two seasons. Its aromatic foliage suggests potential allelopathic or pest-deterrent properties, though these applications remain understudied in permaculture contexts.
Watch out for
In tropical and subtropical climates, Siam weed can self-seed prolifically and spread vegetatively, making it difficult to contain once established in a garden setting. Regular deadheading and monitoring are necessary to prevent unwanted colonization of nearby areas. The plant prefers warm, humid conditions and may struggle or die back in cooler temperate zones.
Overview
- Form
- Growth Rate
- Size
- Dormancy
- Family
- Asteraceae
Native to the United States
Native Range
Central and South America
Native to: Florida, Texas
Seasonality
Bloom Season
Season of Interest
Shrub
Woody multi-stem plants at eye level.
Succession Role
Tolerances & Soil
Establishment & Care
- Establishment
- Maintenance
- Propagation
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.
Climate Match for your location
See how well Siam Weed grows in your area.
Enter your ZIP code and we'll show you how this plant fits your local climate.
Why grow it
Chromolaena odorata establishes quickly in warm climates with minimal inputs, making it useful for rapid biomass production, erosion control, or pioneer plantings on degraded land. Compared to slower-growing native alternatives, it reaches harvestable size within one to two seasons. Its aromatic foliage suggests potential allelopathic or pest-deterrent properties, though these applications remain understudied in permaculture contexts.
Watch out for
In tropical and subtropical climates, Siam weed can self-seed prolifically and spread vegetatively, making it difficult to contain once established in a garden setting. Regular deadheading and monitoring are necessary to prevent unwanted colonization of nearby areas. The plant prefers warm, humid conditions and may struggle or die back in cooler temperate zones.
Overview
- Form
- Growth Rate
- Size
- Dormancy
- Family
- Asteraceae
Native to the United States
Native Range
Central and South America
Native to: Florida, Texas
Seasonality
Bloom Season
Season of Interest
Shrub
Woody multi-stem plants at eye level.
Succession Role
Tolerances & Soil
Establishment & Care
- Establishment
- Maintenance
- Propagation
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