Stachys byzantina aka Lamb's Ear

Stachys byzantina, or lamb's ear, is in the mint family. This plant lives for years. It grows wild from Crimea and northern Turkey to the east. Its range includes the Caucasus and northern Iran. It forms low clumps that spread into a leafy carpet. Gardeners grow it chiefly for its soft, silver leaves. The leaves stay green in warm climates. Harsh winters can leave them worn and damaged.

The leaf mat stands about 0.3–0.5 feet [0.1–0.15 metres] high. Flower stems raise the plant to 1–1.6 feet [0.3–0.5 metres]. Reports note stems reaching 1.7 feet [0.51 metres]. Sources give garden spreads of 1.5–3.3 feet [0.46–1 metre]. Creeping stems root where their nodes, or joints, touch the ground. Thick leaves form rosettes, or rings, at the base. Leaves higher on the stems grow in opposite pairs. Their long, rounded shape gives the plant its common name. Dense, pale hairs coat both the leaves and stems. Stems that stand upright branch and have four angled sides.

Small purple or pink flowers rise above the leaf mat. Two sources give a bloom time of May to July. Chicago Botanic Garden also notes blooms through August. The flowers have two lips and grow in whorls, or rings. These groups form spikes at the stem tips. Butterflies and other pollinators visit the flowers. Flowers may form nutlets once they receive pollen. These small fruits are smooth, brown, and oblong. Some gardeners cut off flower stems for a neater carpet.

Full sun and soil that drains well suit this plant. Light shade in the afternoon helps where summers are hot. Too much shade can keep the woolly leaves damp. It grows in sandy, loamy, or chalky soils. The soil may be acid, neutral, or alkaline. Plants cope with drought once they take root and grow. Too much water invites rot. Sources list USDA zones 4–8 and RHS hardiness H7. It needs little care, though spreading clumps may need splitting. Split clumps in spring or use rooted stem sections for new plants. Sow seeds in spring or autumn.

Lamb's ear suits border fronts, rock gardens, and small ground-cover areas. Its soft leaves suit sensory gardens and pots too. Deer and rabbits tend to leave it alone. Rich soil can help it spread beyond its assigned space. Humid weather and wet leaves can cause rot and leaf spot. Some plants lose leaves in summer even when soil drains well. Slugs, caterpillars, and powdery mildew may cause trouble too. Chicago Botanic Garden reports that this species' extract acts against bacteria. This does not show that home use as medicine is safe. The supplied evidence does not clearly assess whether it is edible or toxic.