An annual or occasional biennial when late germinated seedlings carry through to the following year. It is an ephemeral plant as it can mature and produce seed quickly, giving rise to several generations in a year. As it is a member of the Cruciferae Family and related to the mustards, the leaves are milder in flavour to Rocket, but make a tangy addition to a salad. The seed capsules explode at the slightest touch when they are mature, dispersing their contents widely.
The small, white flowers have four petals and can be found for much of the year.
Height - up to 15 cm.
Hoe or hand pull before flowering, remove uprooted plants if flowers or seed capsules are present. Tackle in early spring to prevent problems later. Also when planting remove the top 3 or 4 centimetres of the compost as most garden centre stock have a ready supply of seed, if not the weeds themselves, dwelling on the surface.
Weedkillers to use:-
A residual herbicide should prevent germination on paths.
Paraquat, Diquat contact action gives an immediate knock-down, so it should not have time to set seed, if caught in time.
Very similar is Wavy Bittercress ( C. flexuosa ) which grows slightly larger - up to 23 cm. The stalks on the leaves do not have hairs and the flowers have six stamens whereas Hairy Bittercress flowers have four, but growth is similar.
The flower stalks and long seed pods are similar to Thale Cress, but the pods on the latter protrude sideways whereas on Bittercress they are more vertical. See also New zealand Bittercress.

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