Spiranthes spiralis

The Spiranthes spiralis, commonly known as the Autumn Lady's-tresses, is a perennial, discreet, autotrophic orchid. Its scientific name (speira = spiral, anthos = flower) refers to the helical or spiral arrangement of its flowers around the stem.

Morphological description: It is a small plant, with an erect stem from 6 to 30 cm, which produces a terminal spike with 10-25 flowers. The flowers are small (approx. 5 mm), bright white and tubular, spurless, and stand out due to a green spot on the labellum with a crystalline, jagged white edge. The flowers emit a vanilla-like fragrance. A distinctive feature is that the new leaves form a basal rosette to the side of the floral stem (not in the center) and remain green throughout the winter (autumn-winter cycle).

Habitat and distribution: It has a wide distribution across Europe, North Africa, and Western Asia. It grows in dry meadows, calcareous grasslands, fixed dunes, and forest clearings, always preferring calcareous soils. It requires conditions of low vegetation (often grazed or mown) to avoid competition with taller plants.

Biologia and distinctive features: It is the last orchid of the year to flower, generally from late August to November. Unlike many orchids, its flowers produce nectar, and pollination is carried out by bees and bumblebees. Like all orchids, it depends on mycorrhizal fungi (like Rhizoctonia) for the germination of its tiny seeds.