Solidago ptarmicoides aka Prairie Goldenrod

Solidago ptarmicoides belongs to the daisy family, Asteraceae. It is a perennial, which means it lives for years. People call it upland white goldenrod or prairie aster. It is native to parts of Canada and the United States. Its range runs from Quebec west to Saskatchewan. To the south, it grows in Georgia, Arkansas, and Colorado. Wild plants grow on prairies and grassy slopes. They also grow on rocky outcrops and in limestone cracks. Other sites include dry, sandy ground. The plant once had the name Aster ptarmicoides. It can cross with other goldenrods, but not with asters.

Plants grow in leafy mounds, not tall, spreading towers. In gardens, they reach 1–2 feet [0.30–0.61 metres] tall and wide. They grow at a moderate rate. The narrow green leaves end in points. Their surface may feel smooth or rough, and hairs occur. Lower leaves have stalks. They reach about 0.58 feet [0.18 metres] long. Leaves become smaller and narrower higher up the stems. Near the top, they have no stalks. These upper leaves also sit farther apart. The stems have no scent.

Flowers open from August through October. They brighten the mound late in the season. Small, daisy-like heads form loose groups with flat tops. Each head has white rays around its centre. The centre is pale yellow or cream. Most groups have three to 25 heads. Some have as many as 50. After bloom, seed heads hold seeds with white fluff. Bees and butterflies visit the flowers, as do other pollinators. The plant also hosts young wavy-lined emerald moths, called larvae. Songbirds eat its seeds, and these birds include goldfinches.

Full sun suits this plant best, though it accepts light shade. It prefers dry sand or gravel in lime-rich soil. It also grows in moist loam if water drains well. It tolerates poor soil and drought. Sources place it in USDA hardiness zones 3–8. It needs little care in dry areas left to grow naturally. It also suits native gardens and gardens for butterflies and pollinators. Gardeners can grow new plants from seed or divide clumps. Remove spent heads before seeds ripen to help limit garden spread. Cut stems back to ground level in late fall.

Serious pest or disease problems are rare, but can occur. Rust, powdery mildew, and leaf spot may affect the leaves. Soil that stays too wet can cause root rot. Beetles and aphids may attack plants. So may insects that form growths called galls. North Carolina lists this species as endangered within the state. This does not show its status across the world. The supplied sources give no evidence specific to this species about its safety as food or toxicity.