Hairy Bittercress (Cardamine hirsuta)

 

Cardamine hirsuta. Frome, 31 March 2021.

A young Hairy Bittercress (Cardamine hirsuta, Sw: Bergbräsma). A pretty sight at this time of year. It's a common weed and one that's very good to eat. It tastes like cress, unsurprisingly. You can eat all of a young plant like this, including the flowers and seedpods. (I'd put it right up there with young Smooth Sow-thistle as the top salad veg in the garden.)

It's very much a plant of Europe and North Africa. It doesn't get very far into Russia. It's native to southern and central Sweden but is only common round the coasts. ("Berg" in the name means "cliff", not "mountain".) I suppose the species struggles to cope with a long winter freeze.

Cardamine hirsuta. Frome, 31 March 2021.

The flowers of Hairy Bittercress have four stamens. Its closest relatives, Wavy Bittercress (Cardamine flexuosa) and Narrow-leaved Bittercress (Cardamine impatiens), have six stamens.

These relatives aren't very likely to turn up in gardens, but some other white-flowered Brassicaceae do: Shepherd's Purse (Capsella bursa-pastoris) has unique purse-like fruits; Common Whitlowgrass (Erophila verna) has split petals and short fruits; Thale Cress (Arabidopsis thaliana) has entire leaves. 

Not that it matters too much from the eating point of view: all members of the Brassicaceae family are edible by humans. (The plants are more concerned with deterring insects and other herbivores.)

Cardamine hirsuta. Frome, 31 March 2021.

As the plants grow older they elongate like this. Not quite so delicious, but still pretty good.

If you want them out of your garden, you need to pull up the Hairy Bittercress plants when they're young. Like any self-respecting annual weed, Hairy Bittercress doesn't hang around when it comes to ripening seed. If you leave it a week or two, all the seedpods will explode as soon as you touch the plant, showering seeds everywhere. 

Repellently, the gardening advice for Hairy Bittercress on the RHS website still lists various brands of weedkiller as an alternative to weeding. Apart from the evil effects of using such products -- why mince words? -- it's particularly pointless in this case, when the plants pull out so easily. (If you did use weedkiller you'd surely want to pull up the dead plants anyway, not just leave them there, so what effort have you saved yourself?)