Euthamia graminifolia aka Common Goldentop

Euthamia graminifolia belongs to the daisy family, Asteraceae. It is a perennial, so it lives for years. Its common names are grassleaf and flat-topped goldenrod. Its old name is Solidago graminifolia. Its native range starts in subarctic North America. It reaches into the west-central and east-central United States. It is not native to Britain or Ireland. It grows in meadows, thickets, and along shores. These sites range from damp to somewhat dry.

The plant grows upright and looks like a shrub. Garden sources give heights of about 3–5 feet [0.9–1.5 metres]. Chicago Botanic Garden gives heights near the low end. Plants For A Future gives the taller height. Its narrow, bright green leaves have smooth edges. Small leaf glands help tell this genus apart from Solidago. Work on genes also backs this split. Small yellow flowers grow in flat groups near branch tips. Each flower has both male and female organs. Insects carry pollen between the flowers.

Sources give bloom times from July to October, but differ. Chicago says blooms start in early August. Plants For A Future gives September through October. The plant suits full sun but tolerates light shade. It prefers moist soil that holds water. The soil should have a fair level of nutrients. It grows in sand, loam, and heavy clay. It suits soils with a mild acid or alkaline pH. Neutral soil suits it too. Chicago lists USDA hardiness zones 2–6. Its native range has a temperate climate and includes cold northern regions.

Gardeners can grow this goldenrod in beds and borders. It draws birds, butterflies, and insects that help the garden. Ladybirds, lacewings, and hoverflies visit and help keep pests in check. Its spread can cause trouble in planted beds. Plants For A Future warns that it can become invasive. That source also notes that it can drain soil nutrients. Growers can sow its seeds in spring. Give seeds a light soil cover and keep compost moist. Growers can also divide plants in spring or autumn.

Fresh or dried leaves can take the place of tea. The whole plant yields mustard, orange, and brown dyes. Records describe past uses of roots, flowers, and dried herbs. People used these for fever and chest or lung complaints. These records do not prove that the treatments work. Plants For A Future lists no known hazards. This alone does not mean it is safe for people or pets.