Ageratum conyzoides - Goatweed

Habitat

Exposition

Plein soleil

Humidité

Humidité moyenne.

Sol

Tous sols.

pH

Sol acide ou calcaire

Rusticité

Zone 9

Habitat originel

A common weed of cultivated ground, having spread from its native range to all areas of the Tropics within 20° of the Equator, to an altitude of 2,500 metres[200].

Origine géographique

S. America.

Usages médicinaux

• The juice of the root is antilithic [240, 243].
• A paste of the root, mixed with the bark of Schinus wallichii, is applied to set dislocated bones [272].
• The leaves are styptic [240].
• They are dried and applied as a powder to cuts, sores and the ruptures caused by leprosy[272], The powder absorbs the moisture of the disease and forms a layer that is removed after 1 - 2 days [272].
• An effective cure for most cuts and sores, though it does not effect a complete cure for leprosy [272].
• The leaves are also used externally in the treatment of ague [240, 243].
• The juice of the plant is used to treat cuts, wounds and bruises [272].
• A paste of the leaves is used as a poultice to remove thorns from the skin [272].
• A paste made of the leaves mixed with equal amounts of Bidens pilosa, Drymaria cordata, Galinsoga parviflora and the rhizome of Zingiber officinale is used to treat snakebites [272].
• The juice of the flowerheads is used externally to treat scabies, whilst a paste of them is used to treat rheumatism [272].
• A tea made from the flowerheads mixed with Ocimum tenuifolium is used to treat coughs and colds [272].

Autres usages

• The leaves and the flowers yield 0.2% essential oil with a powerful nauseating odour [240].
• The oil contains 5% eugenol, which has a pleasant odour [240].
• The oil from plants growing in Africa has an agreeable odour, consisting almost entirely of eugenol [240].

Culture

• Succeeds in full sun in a sheltered position in any reasonably fertile moisture-retentive soil that does not dry out in the summer [200].
• Plant vigour and flowering periods are much reduced on dry soils [200].
• This species is not frost hardy, though it can be grown as a summer annual in Britain [200].
• The fresh plant is malodorous [200].

Propagation

• Seed - sow late winter or early spring in a warm greenhouse and only just cover the seed .
• Prick out the seedlings when large enough to handle and plant out after the last expected frosts [200].
• Seed can also be sown in situ in the spring and, for earlier blooms, it is possible to sow it in late summer or early autumn, though it will need to be overwintered in a warm greenhouse [200].