Persicaria decipiens (POLYGONACEAE) Slender Knotweed

Plants to Plant

Persicaria decipiens is an annual or perennial herb found all throughout the Australian mainland and New Zealand. Sparingly branched, slender stems to 60 cm long. The stems spread along the ground and root at the base then gradually slope upwards. Leaves are shortly stalked and are lance shaped with long, pointed tips. The leaf sometimes has hairs along the veins on the lower surface wide. The leaf margins are stiff, hairy, green and often have a black notch near the middle. This genus has a distinctive characteristic of sheathing outgrowths at the base of the leaf stalk. Flowers are slender and situated at the end of the main and side branches. The whole flower is between 2.5-3.5 mm long with the tube greenish and shorter than the lobes, which are pale to deep pink and sometimes white. Fruit is approximately 3 mm long, solidly triangular, dark brown and shiny.

This could be one of the other Persicarias, hard to tell from this photo. Photo: Robert Whyte