Anthemis cotula aka Chamomile

Anthemis cotula is an annual in the daisy family, Asteraceae. Its names include mayweed, stinking chamomile, and poison daisy. It comes from much of Europe, including Britain. Its native range runs east into northern and western Asia. It grows on waste ground, often in heavy soil. Its strong, unpleasant smell helps set it apart from similar plants.

The plant branches freely and has a spreading form. The RHS describes plants about 2 feet [0.6 metres] tall. Its size table gives 1.6–3.3 feet [0.5–1 metre] for height and spread. Bright green leaves have pinnate lobes, giving them a divided look. The foliage is deciduous. Daisy-like flowerheads appear through summer and have a strong scent. Each head can reach about 0.1 feet [0.03 metres] across. White ray flowers surround a yellow central disk. The rays spread out at first, then bend back.

Grow this plant in full sun with very good drainage. The RHS lists chalk, loam, and sand as suitable soils. It accepts acid, neutral, and alkaline ground. Sandy or gravelly soil suits its need for sharp drainage. It can grow in dry to moist conditions. The RHS gives it a UK hardiness rating of H6. Plants For A Future lists USDA zones 4–8. Raise new plants from seed; they need no pruning.

The RHS suggests it for wildflower meadows and wildlife gardens. Plants For A Future also records its use in planted beds. Yet it flags the species as a potential weed. Slugs and aphids may attack it, and powdery mildew may occur. The whole plant can yield a gold dye. Reports also describe fresh or dried plants as flea and mouse repellents. These are recorded uses, rather than proof of reliable pest control.

Plants For A Future lists leaves as edible and flowers for tea. It also records use of the herb as flavouring in Peru. These uses come with clear safety concerns, not a food recommendation. Touching or eating the plant can cause allergic reactions in people. It has past herbal uses but sees little use today. The ASPCA lists it as toxic to dogs, cats, and horses. Signs include skin irritation, vomiting, loose stools, and poor appetite. Allergic reactions can occur, and prolonged use may increase bleeding risk.