Pterostylis aestiva

Pterostylis aestiva, commonly known as the long-tongued summer greenhood, is a species of orchid endemic to south-eastern Australia. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering spike.

Description
Pterostylis aestiva is a terrestrial, perennial, deciduous, herb with an underground tuber and when not flowering, a rosette of dark bluish-green leaves, each leaf 10-30 mm long and 10-15 mm wide. Flowering plants have a single flower 20-30 mm long and 7-9 mm wide borne on a spike 150-350 mm high with between three and five stem leaves. The flowers are dark bluish-green, white and brown. The dorsal sepal and petals are fused, forming a hood or "galea" over the column. The dorsal sepal curves forward with a thread-like tip 8-12 mm long. The lateral sepals are held closely against the galea, have an erect, thread-like tip 25-35 mm long and a protruding sinus between their bases. The labellum is 15-19 mm long, about 4 mm wide, brown, blunt, and curved and protrudes above the sinus. Flowering occurs from January to April.

Taxonomy and naming
Pterostylis aestiva was first formally described in 1972 by David Jones from a specimen collected near Wulgulmerang. The description was published in Muelleria. The specific epithet (aestiva) is a Latin word meaning "pertaining to summer".

Distribution and habitat
The long-tongued summer greenhood grows among grasses in high rainfall forests in north-east Victoria and New South Wales as far north as Mount Canobolas.

Use in horticulture
This greenhood is easily grows in pots although plants must be kept moist during the growing season and dry when dormant.