Alisma plantago-aquatica, also known as European water-plantain, common water-plantain or mad-dog weed, is a perennial flowering aquatic plant that grows in shallow water, and consists of a fibrous root, several long stemmed, and a triangular branched stem bearing numerous small flowers with white or lilac-coloured petals. The flowers open in the afternoon. It flowers from June until August.

Type: Hardy perennial

Hardiness zones: 4-8

Height: 36", 90cm

Location: Sun

Seeds per packet: 100

By Bff - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=9697386