Smelly South American invader strikes
Woolly nightshade, also known as tobacco weed, is a capsicumsmelling South American invader that can particularly damage farm pasture and prevent the establishment of native plants beside waterways.
It can also pose a threat to human and soil health.
Unfortunately it has made itself right at home in the northern areas of New Zealand and is seeking to expand its territory further down the country wherever it can find a climate pocket that suits.
It seems to especially love conditions in the Waikato as it can grow to 10 metres tall here.
This pest has soft stems and large, velvety light green leaves that are whitish underneath. Clusters of purple flowers develop into large round berries.
Woolly nightshade can pop up in gardens at any time. It grows and matures rapidly, forming dense tall stands and producing many well-dispersed seeds most of year.
The plant is covered in a fine dust that can causes allergic reactions or rashes in some people. It also produces toxins that poison the soil around it, stopping other seedlings from establishing.
Woolly nightshade is not fussy about conditions, tolerating wet and dry, salt, hot to cool temperatures, semi-shade, damage and grazing.
Seedlings can be pulled out by hand. Larger plants can be cut down and the stumps immediately painted with a suitable herbicide or sprayed.
As a replacement for cleared areas, try the native Brachyglottis repanda which also has large, attractive leaves, or the striking lasiandra which has large leaves and purple flowers.