Polystachya ottoniana is an epiphytic orchid, growing from a stout, woody rhizome attached to tree trunks and sometimes to rocks. A well developed cluster of swollen, pale green or creamy yellow pseudobulbs can be observed in this photo, taken in November at Ixopo in southern KwaZulu-Natal. The pseudobulbs are ovoid, about 2 cm long, a couple of green leaves emerging from the top of each in season. Terminal spikes of white or cream flowers are produced.
The species distribution ranges from the Western and Eastern Cape through KwaZulu-Natal and Mpumalanga to Limpopo. Across the border it grows in Swaziland, Mozambique and further into tropical Africa.
The habitat is riverine forest and woodland from the coast to elevations of 1600 m. The species is not considered to be threatened in its habitat early in the twenty first century (JSTOR; iSpot; www.orchidspecies.com; www.redlist.sanbi.org).