In New Zealand we call this plant Onion weed but, here in Britain, its common name is Three-cornered leek. As its scientific name, Allium triquetrum, indicates, this bulbous plant is part of the garlic and onion family, the Alliums, and triquetrum refers to the triangular shape of its flower stem.
In Flora Britannica, Richard Mabey writes that this smelly plant was ‘introduced to Britain in 1752’ and ‘began to escape into shady hedge-banks and churchyards in Cornwall in the 1860s. By the 1930s it was in Devon’ and, in 1995, Mabey found it in the Chilterns, near London. Obviously, it’s spread even further since then, as it’s jumped the border and is thriving here in Wales. These were my first Three-cornered leek flowers for 2020.