Spiranthes spiralis aka Autumn Lady's Tresses Spiranthes

Spiranthes spiralis is a small orchid called autumn lady's tresses. It belongs to the orchid family, Orchidaceae. Its native range spans Europe, north Africa and western Asia. It is native to Great Britain and Ireland too. This herbaceous perennial grows from tubers beneath the soil. In the wild, it grows in open, grassy meadows. It also occurs in dry, rocky grassland with poor soil.

The plant has an upright form and grows slowly. Its flower stem measures about 0.33–0.5 feet [0.10–0.15 metres]. The round stem is grey-green, with short glandular hairs above. Its leaves form low rosettes close to the ground. Each rosette holds four or five simple, grey-green leaves. These have an ovate shape, pointed tips and smooth edges. They attach without leaf stalks. Leaves measure about 0.08–0.13 feet [0.025–0.038 metres] long.

Small white flowers wind around the stem in a spike. They open from late summer into autumn and have scent. Each flower has a hooded, tubular shape. A green mark sits on the lower lip. The lip also has a frilled edge. Oval seed capsules follow the flowers and contain many tiny seeds. The capsules provide a winter fruit display. The spiral flower pattern gives this small plant its main visual interest.

Its growth cycle includes a summer rest in June or July. A flower stalk emerges toward the end of summer. One or two leaf rosettes then appear shortly afterward. These leaves last through winter and spring. Young tubers may take years to produce their first leaves. Flowering can take another three years after that. Mature plants may flower only once every two or three years. Poor conditions can keep all growth below ground. A year without visible shoots need not mean the plant has died.

For cultivation, it prefers full sun but also accepts partial shade. It needs good drainage and can tolerate dry soil. The listed soil range includes clay, loam and sand. Alkaline soil suits it, with moisture ranging from moist to occasionally dry. North Carolina State lists USDA hardiness zones 5–9. Meadow and naturalized settings match its habitat. Yet the same source describes it as rarely offered for gardens. It also notes threats in parts of its native range.