Most sun orchids close their flowers at night, in cloudy or cool weather, giving rise to their common name.

Orchids in the genus Thelymitra are terrestrial, perennial, deciduous, sympodial herbs usually with a few inconspicuous, fine roots and a pair of oval-shaped tubers.

[2][3] The inflorescence is a raceme with from one to many resupinate flowers with three sepals and three petals all more or less alike in size, shape and ornamentation.

The flowers of most species only open in bright warm sunlight and close at night or during cold or cloudy weather.

There are about 100 species distributed in higher rainfall areas of Australia, 15 in New Zealand, 11 of which are endemic, one in New Caledonia, one in East Timor and one in Java and the Philippines.

[16] Thelymitras can be grown in a freely draining, dense mixture with partially composted organic matter.

It is good practice to cover the surface in pine or she-oak needles to control water loss and to feed the mycorrhizal fungi that support the orchid.