Its habitat is mountain forests and more open woodland up to 3000 m, but it can descend to 1300 m in the wet season. The white eggs are laid in an unlined nest cavity 8-20 m high in a tree, which may be an old woodpecker hole or a broken stub.
The Sulphur-winged Parakeet is 23 cm long and weighs 75 g. The adult is mainly green. scaled with orange on the head and chest. There is a red nape spot and the tail is dull red. The outer primaries of the wing are blue, but the most obvious feature in flight is the extensive yellow on the inner wing. Young birds are similar to the adults, but duller and with much less yellow in the wing.
Sulphur-winged Parakeet feeds in flocks of 5-15 birds at treetop level, taking various seeds and fruits including figs. Its flight call is a grating toweet-deet-deet-toweet, and when perched it has a reedy zeeweet.
This parakeet is named for the German naturalist Karl Hoffmann.