Erect bushy perennial, with long spikes of pink, showy flowers. Stems single, or branching near the top. Spikes measured to 40 cm long, flowers measured to 2 cm diameter. Leaves opposite, lanceolate, sessile, leaf measured at 11 cm long and 2.5 cm wide. Stems square. Stems, leaf top and bottom all pubescent.

Invasive, non-native, noxious weed. Is native to wetlands in Europe, and it's to wetlands where it poses a risk in North America.

In our city, is invading wetlands via storm sewer outlets, evidence of seed washed there from city gardens. If you're growing this in a North American garden, shame on you. It's likely well behaved in your garden, but it's in the stream or marsh a kilometre away from your garden where it will spread.

I measured plants growing to a height to 150 cm.

Took the above photos August 18th along a stream in the Wood Meadows subdivision in Regina, SK, about 150 metres away from a selfish idiot who's growing it in their garden.