Fallopia japonica × sachalinensis (= Fallopia ×bohemica)
Other Common names: Japanese knotweed, Mexican bamboo
Polygonum cuspidatum, Polygonum reynoutria, Fallopia japonica, Fallopia japonica x sachalinensis, Fallopia x bohemica
Asiatic knotweed is an upright shrublike herbaceous perennial that can rapidly grow to 3 m in height. It has red-purple shoots which appear early in spring but, as the canes grow, the leaves unfurl and the plant turns green. The mature canes are hollow and have a characteristic pattern of purple speckles. The leaves are long and triangular (15 x 10 cm) and pointed at the tip, with a characteristic flattened leaf base. In late summer it produces masses of creamy white flowers.
Once established, Asiatic knotweed forms dense stands that shade and crowd out all other vegetation, displacing native flora and fauna.
What to do
Contact your regional council to determine the status of this species and responsibility for control and/or advice on control.
Page last updated: 14 January 2010