More often overlooked as a weed growing close to water and on arable land, this is an annual which is identified mainly by the dark blotch on its leaves. Standing up to 80 cm tall, this plant bears its bright pink, rarely white, flowers in cylindrical, densely-crowded spikes on reddish stems. Each tiny flower has no petals but has 4–6 petal-like sepals and they bloom from June to October. The leaves are 7–10 cm long, lanceolate, downy on the undersides and bear the distinctive blotches on the uppersides. In autumn, the tiny, black seeds of this wildflower attract many small birds. This is a widespread native plant, also known as Spotted Persicaria and Lady's Thumb and and it belongs to the Polygonaceaefamily.
My earliest record of this plant is in1976 at Roundwood, County Wicklow and I photographed it at Vicarstown, County Kildare in 2004. I came across the white version while on a stroll in Galway city in 2009.
If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre