Galeopsis angustifolia

About

Galeopsis angustifolia, red hemp-nettle, is an annual plant that is native to western Europe and increasingly occurs as a casual in eastern Europe. Its wild habitat is in montane scree in the Alps and Pyrenees, or on coastal shingle, but it is widely established on waste ground, arable fields and gravelly substrates. It was much more common on farmland in the past, where it was sometimes confused with Galeopsis ladanum.

Summary from Wikipedia