Blue Billygoat Weed/Goat weed/ flossflower/ bluemink/ blueweed/ bluetop (Ageratum houstonianum) A short-lived, perennial plant that emerges and flowers all year round. The tiny, ray flowers are pale lavender blue and occur as showy, fluffy clusters on ends of erect stems. The seeds are black and attached to whitish fluff that assists in wind dispersal. Leaves are mid-green, ovate to triangular in shape and serrated at the margins. Tiny hair cover the leaves and the leaf-stalk. Stem is reddish and hairy. The plant is generally about a foot high but can reach upto 3 feet.The leaf oil has anti-bacterial and insecticidal properties. Leaves exude a distinctive odour when crushed. The plant flourishes in wastelands, on the road-sides and degraded and overgrazed pasteurs. It can grow even under poor light conditions. It is treated as an ‘environmental weed’ in Australia as it can disrupt growth of native flora.
- Moreton Bay Regional Council’s factsheet on Blue Billygoatweed