Parietaria judaica aka Spreading Pellitory

Parietaria judaica is a herbaceous perennial in the nettle family, Urticaceae. Its common names include pellitory-of-the-wall and murlys. Its native range spans Macaronesia, North Africa, and much of Europe. It extends east to Central Asia and the central Himalaya. The RHS lists it as native to Britain and Ireland. It grows there on walls, rocks, cliffs, and steep banks.

The plant has a bushy, sprawling shape and sheds its leaves. Its stems reach about 1.3 feet (0.4 metres) long. Narrow, oval leaves have a dark green shade and clear veins. Short, soft, white hairs cover all parts of the plant. Tiny red flowers form rings around the stems. They appear from midsummer into autumn. Though related to stinging nettles, this plant has its own garden role. Red admiral caterpillars feed on it.

It grows in full sun or partial shade. It accepts chalk, loam, and sand, but needs good drainage. Acid, neutral, and alkaline soils all suit it. The RHS records drought resistance and tolerance of dry to moist soil. Both open and sheltered sites can suit the plant. Its H4 rating means it withstands most UK winters. That rating covers minimum temperatures from about −10 to −5°C. The RHS gives two to five years as its time to maturity.

Its natural sites offer a guide to garden placement. Rock gardens, gravel beds, and banks can suit its loose form. It also fits informal borders and beds beside walls. In the wild, it occupies rubble, paving cracks, and old masonry. Gardeners can raise it from seed or divide established plants. It needs no routine pruning, according to the RHS. That source also reports few usual pest or disease problems. PFAF does not flag it as a weed.

PFAF lists the leaves and young shoots as edible. People eat young growth raw or cooked, including in mixed salads. It also records a long history of herbal use. These uses include urinary complaints, coughs, wounds, and burns. Such records describe traditional use rather than proof of treatment benefits. PFAF reports no known hazards, but its supplied medicinal warning is incomplete. This evidence therefore does not establish safety for every person or pet. A separate household use employs the whole plant to clean glass and copper vessels.