Kōwhai are small woody legume trees within the genus Sophora that are native to New Zealand. There are eight species, with Sophora microphylla and S. tetraptera being the most recognised as large trees. Their natural habitat is beside streams and on the edges of forest, in lowland or mountain open areas. Kōwhai trees grow throughout the country and are a common feature in New Zealand gardens. Outside of New Zealand, kōwhai tend to be restricted to mild temperate maritime climates.

The blooms of the kōwhai are widely regarded as being New Zealand's national flower,although they have no official status as such.