This hairy perennial, also known as Downy Pepperwort, is widespread throughout Scotland, except for the far North and Isles.
It grows in disturbed and cultivated ground and along waysides. Smith’s Pepperwort is one of around 200 species in the genus Lepidium, all of which belong to the cabbage family and include cresses and grasses of all kinds. Lepidium even includes tumbleweed in the US.
The plant has narrow and toothed leaves with rounded ends, which cluster around and clasp the stem all the way up to the flower head. Both leaves and stem are hairy.
The flower head is a blunt raceme crowded with small white flowers, about 4-5mm in diameter. Each flower has 4 separated petals, and 6 stamens with white filaments and purple anthers. A green ovary protrudes slightly from inside the flower with a white-tipped style.
When the ovaries develop into fruits each bears 2 seeds, and looks like a flattened oval, about 4-5mm in length, with a ridge up the middle, not dissimilar to Shepherd’s Purse, which belongs to the same family, though Shepherd’s Purse fruits are more heart-shaped. The fruits of the Lepidium tend to curve upwards on their stalks, sometimes with the oval fruits bending into shallow bowls, instead of sticking out at right-angles to the stem as do those of Shepherd’s Purse.