Perennial, speading by seed which are carried by the wind from the upright seed pods, as they split lengthwise and curl open - although most fall close to the parent plant. The leaves are finely toothed with no hairs, arranged alternately near the top of the stem and opposite lower down. The round stem is hairless, but no has raised lines and dies away in the late autumn, and the plant overwinters as leafy buds at the base. Some of the buds grow sideways on the surface and take root to form a larger clump in subsequent years.
One of the problem weeds in borders and on paths; often found in cracks, crevices and in gutters which provides a perfect launchpad for the seed.
Flowers from June to August - small pale pink at the tip of a slender ovary. The four petals have a deep notch and the stigma has four lobes.
Height - up to 60 cm.
Hoe or hand pull before seed set. Often snaps at soil level, then regrows with 3 or 4 new shoots.
Weedkillers to use:-
Dichlobenil prevents emergence of seedlings among established woody plants, for up to one year.
Paraquat, Diquat kills top growth on contact, use at seedling stage.
Glyphosate, systemic action killing the whole plant.

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