Lepidium ruderale aka Narrow Leaf Pepperwort

Lepidium ruderale is known as narrow-leaved pepperwort. It belongs to Brassicaceae, the cabbage family. Its native range covers temperate parts of Europe and Asia. The RHS lists it as native to Britain and Ireland. It grows as an annual or biennial herb. An annual completes its life in one growing season. A biennial lives through two growing seasons before it dies.

This small plant reaches about 1 foot [0.3 metres] tall. Plants For A Future records flowers from May to July. Each flower has both male and female organs. The plant is self-fertile, so it does not need another plant for fertility. The supplied sources give no detail on flower colour or fruit. They also give no account of its stems or leaf shape. Its small size is the main guide to its garden form.

In the wild, it grows on waste ground and roadsides. The British habitat account places it near the sea. It singles out East Anglia as a place to find it. In gardens, it grows in beds and accepts most soils. These include sand, loam, and clay. It tolerates mildly acid, neutral, and mildly alkaline ground. It can grow in full sun or light shade. Plants For A Future says it prefers moist soil. The same source describes it as easy to grow. It also states that frost does not harm it.

Young leaves are edible, either raw or cooked. They have a sharp taste like cress. Plants For A Future gives its food value two out of five. Its use as a leaf crop is better documented than ornamental value. That source lists no other non-medicinal uses. To raise plants, sow seed where it will grow. Spring and late summer are the stated sowing times. Seeds should sprout within three weeks under the conditions described by that source.

Plants For A Future records a medicinal use for impetigo. It also reports that a water extract lowers blood pressure. That extract can slow breathing, which warrants caution. These records do not establish a safe home treatment. The source lists no known hazards for the plant. That statement does not prove safety in every use. The supplied evidence gives no specific pest or disease guidance.