They were brought to North America in the late 1600's as an agricultural crop for forage and honey production. These clovers also fix nitrogen, and thus became popular as soil enhancers. The chemical used in the production of the blood thinner Warfarin was first discovered in sweet clover. Due to the economic values of white and yellow sweet clover, these species will continue to be planted despite the problems they pose for land managers. Both species are found in all fifty states, although they are most frequently found in the states of the Upper Midwest and Great Plains.
Sweet clovers grow well in direct sunlight or in partial shade.
Neither species can tolerate complete shade. Sweet clovers seem to prefer calcareous or loamy soils, and are most frequently found in open, disturbed, upland habitats such as prairies, savannas, and dunes. Sweet clovers are fire-influenced, aggressive, weedy plants that produce populations with high rates of fluctuation. Both species degrade native grasslands by overtopping and shading native sun-loving species. Both white and yellow sweet clovers are biennials.