Siam Weed
Image: Thilanka and Nimali (cc-by-nc)
NameSiam Weed
Scientific NameChromolaena odorata
Common NamesSiam Weed, Bitter Bush, Christmas Bush, Jack-in-the-bush, Triffid Weed
Plant FamilyAsteraceae
Natural HabitatNative to Central and South America, but widely naturalized and invasive in tropical and subtropical regions worldwide, including Asia and Africa. Thrives in disturbed areas, roadsides, agricultural lands, and forest edges.
Parts Usedleaf,flower,whole_plant
Medicinal Actionsanti-inflammatory,antimicrobial,antioxidant,astringent
Traditional UsesTraditionally used for wound healing, cuts, burns, and skin infections due to its antiseptic and astringent properties. In some folk medicine systems, it is also used internally for fever, coughs, and gastrointestinal issues, though external application is more common and well-documented.
Active ConstituentsFlavonoids, Alkaloids, Essential oils, Tannins, Saponins
Preparation Methodspoultice,infusion,decoction,powder
Contraindications & WarningsCan cause allergic reactions in sensitive individuals. Internal use should be approached with caution due to potential toxicity and lack of extensive safety data. May interact with blood-thinning medications.
Cultivation NotesHighly adaptable and invasive, Siam Weed propagates readily by seed and vegetatively. It prefers full sun to partial shade and a wide range of soil types, thriving in warm, humid conditions. Often considered a weed and can be difficult to control.
Raritycommon
Description
A fast-growing, perennial, herbaceous shrub or subshrub, typically reaching 1-3 meters in height. It features numerous small, white to pale lavender flower heads clustered in terminal corymbs, and ovate to triangular leaves with serrated margins.
