Oenothera is now an expanded genus, with the recent inclusion of Gaura. Both of which are native to New World, growing in open sandy and rocky areas, occasionally by streams. Annuals or perennials, with delicate 4-petalled flowers, a variety of colours in the old Oenothera genus, within the old Gaura, flowers typically white to pink. Flowering normally in summer.
The flowers of the majority of species are most open and fragrant in the evening when they are visited mainly by the wasps and moths that are active at that time of the day. Some forms, especially those formerly called Gaura, flower by day and are much visited by both bumblebees and butterflies. In autumn, if they are not 'tidied up', the spikes of seed pods may be visited by goldfinches and other seed-eaters. Several species and hybrids are now to be found naturalized widely, especially in the lowlands of England and Wales, on brownfield sites and sand-dunes.