This plant grows in many types of shrubland and grassland habitat, as well as in some cultivated areas.

It occurs on cinder cones and offshore islets and exposed coral reefs.

[1] Vigna owahuensis is an annual or perennial herb growing up to 40 cm (16 in) long.

The fruit is a long, thin legume pod up to 9 cm (3.5 in) in length.

Two of the seven populations are on Molokai, one occurring in a plantation of tropical ash and pine trees.