Liatris spicata aka Dense Blazing Star

Liatris spicata is a perennial in the daisy family. Gardeners know it as blazing star or spike gayfeather. Its native range spans eastern Canada and central to eastern United States. It grows in meadows, low ground, and near marshes. Plants form upright clumps from corms with shallow, fibrous roots. New shoots can spread from these corms to form colonies.

Garden plants often reach 2–4 feet [0.61–1.22 metres] tall. Some sources report heights of 6 feet [1.83 metres]. The RHS gives a shorter range of 1.6–3.3 feet [0.5–1 metre]. Clumps spread to about 1.6 feet [0.5 metres] wide. Narrow green leaves form a tuft at the base. These leaves can reach 1 foot [0.30 metres] long. Stiff, leafy stems rise above them and carry flower spikes. The foliage dies back at the end of the season.

Rounded purple flower heads give the spikes a soft look. Each spike measures about 0.5–1 foot [0.15–0.30 metres] long. Flowers open first at the top, then farther down. July and August are the main bloom months. Some garden records extend flowering into September and October. Bees and butterflies visit the flowers for food. Goldfinches eat the seeds, while moth larvae feed on the plant. Native bees also nest within its dead, hollow stems.

Full sun and moist soil suit this plant best. It needs good drainage, with no wet soil through winter. It tolerates poor soil, clay, drought, summer heat, and humidity. Still, fertile soil with steady moisture gives better results. It grows across acidic, neutral, and alkaline soils. Hardiness ratings cover USDA zones 3–8 and RHS H7. Grow it from seed or divide clumps in spring. Seed-grown plants can take time to become established. Tall stems may lean and need support. Sources report few serious pest or disease problems.

Use blazing star in borders, prairie beds, and rain gardens. Groups also fit native, cottage, and pollinator gardens. Its stems provide flowers for fresh or dried arrangements. Deer cause less damage than they do to many plants. PFAF records no known food use for this species. Native Americans used its roots in traditional medicine. Leaves and roots also feature in scented and insect-repellent mixtures. PFAF notes a report of coumarins in the leaves. These compounds can reduce blood clotting, so food safety remains uncertain.