Pterostylis patens, commonly known as
tutukiwi or
greenhood, is a terrestrial,
perennial,
deciduous,
herb with an underground
tuber. Both flowering and non-flowering plants have between four and six erect, lance-shaped leaves which are long, wide and grass-like. Flowering plants have a single green flower with white stripes which is prominently inflated near its base. The
dorsal sepal and
petals are fused, forming a hood or "galea" over the
column. The dorsal sepal is tall and curves forward then downward, tapering to a thin tip long. There is a wide gap between the galea and the lateral sepals which spread apart from each other, with long, thread-like tips up to long which sometimes almost meet behind the ovary. The
labellum is flat in cross-section gently curved and protrudes above the
sinus between the lateral sepals. Flowering occurs from February to April. ==Taxonomy and naming==