Glechoma hederacea aka Ground Ivy

Glechoma hederacea is ground ivy, also called creeping Charlie. This evergreen perennial belongs to the mint family, Lamiaceae. Its native range runs from Europe to Siberia and Xinjiang. It is native to Britain and Ireland. People brought it to the United States for food and medicine. It now grows across much of that country. It occurs in lawns, roadside ground, thickets, and woodland edges.

Ground ivy grows fast and forms a low, spreading mat. RHS gives a garden height of 0.3–1.6 feet [0.1–0.5 metres]. It gives the same range for spread. NC State describes plants reaching 1 foot [0.3 metres] or less. RHS places flowering stems at about 0.3 feet [0.1 metres]. Square stems creep across the soil and root at leaf nodes. Fine hairs cover parts of the stems and leaves. The green leaves grow in opposite pairs on long stalks. They are round to kidney-shaped, with scalloped edges. Crushed leaves release a strong scent.

Small, blue-violet flowers grow in clusters where leaves meet stems. RHS also records pink and white flowers within the species. Each tubular flower has two lips and darker nectar guides. The broad lower lip gives visiting insects a landing place. Long-tongued bees and other pollinators feed on the nectar. NC State gives April to June as the flowering season. PFAF instead lists mid- to late-summer bloom. Each fruit divides into four small, dark brown nutlets.

Grow it in moist soil that drains well. RHS accepts full sun or partial shade. NC State notes a preference for shade and fertile loam. RHS lists clay, chalk, loam, and sand as suitable soils. It rates the plant H6 for UK hardiness. NC State lists USDA zones 3–10. Plants may become dormant during hot summer weather. Ground ivy can cover banks and ground beneath shrubs. It also suits wildlife gardens and shaded woodland edges. Divide plants in spring or autumn to make more. Softwood cuttings offer another method in late spring.

Its spread can crowd out smaller plants and invade lawns. NC State records it as invasive in parts of the United States. Cut it back as needed to limit its reach. Slugs and snails may attack it, but disease problems are few. People eat the bitter leaves raw or cooked. They also use fresh or dried leaves for tea. The herb once flavoured beer before hops became widespread. Sources record traditional medicinal uses, not proof of treatment benefits. It is toxic to horses. PFAF warns against use during pregnancy, epilepsy, or kidney disease.