Erigeron glaucus aka Seaside Daisy

Erigeron glaucus is a low, evergreen plant in the daisy family, Asteraceae. Gardeners know it as seaside daisy or beach aster. Its native range runs from Oregon south into California. It grows on sea bluffs and sandy beaches along this coast. Kew classes it as a subshrub from a temperate climate. The RHS describes its garden habit as a clump-forming perennial. It is not native to Britain or Ireland.

The plant forms low clumps of grey-green, lance-shaped leaves. These leaves stay on the plant through the year. The RHS gives one size of 0.7 feet (0.2 metres) tall. That description gives a width of 1 foot (0.3 metres). Its broader garden range reaches 1.6 feet (0.5 metres) tall. Spread can reach 3.3 feet (1 metre). These figures allow for plants larger than the compact description suggests. Plants take two to five years to reach full size.

Summer flowers have mauve petals around a yellow centre. Their colour stands above the muted green leaves. Remove spent flowers to help the plant bloom again. The RHS also recommends cutting growth to ground level in autumn. This helps keep the clump neat. Make new plants by division or by taking basal softwood cuttings. Take those cuttings from mid- to late summer.

Choose full sun and fertile soil that drains well. The soil should not dry out during summer. The RHS lists clay, chalk, loam and sand as suitable soils. It also accepts acid, neutral and alkaline conditions. Plants can grow in exposed sites or sheltered spots. South- and west-facing sites suit their need for sun. Coastal gardens suit this species well. The RHS rates it H5 for UK winter hardiness. Plants For A Future lists USDA zones 3–7. These ratings use different systems and should be read in context.

Use seaside daisy along bed edges or as ground cover. It also suits banks, slopes, gravel gardens and informal borders. The RHS lists it for planting beneath roses and shrubs. Plants For A Future suggests ground-cover spacing of 1.5 feet (0.45 metres). Both sources include uses in gardens that support wildlife. The RHS reports few usual pest or disease problems. Plants For A Future does not flag it as weedy. That source records no known food or medicinal uses. It also lists no known hazards. This does not establish that the plant is safe to eat.