Common Hemp-nettle is an erect, annual species that grows up to about one metre in height, flowering from July to September on rough and waste ground, hedgerows and is also found on arable land. It bears its flowers in a terminal spike, in a whorl. These are each 13 – 20 mm long, pinkish-white with purple squiggles on yellow patches in the three-lobed lower lip and a creamy-yellow hood-like upper lip. There are four stamens, two long and two short. The calyx is quite hairy with long teeth – this is where a hand lens is most useful. The leaves are from about 3 to 10 cm long and toothed. The stems are hairy also. The plant has an unpleasant smell. This is a native species and is relatively widespread in south-east Leinster and in Ulster.
I came across this in Roundwood, Co Wicklow in July, 2025 on the hottest day of the year!
If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre
