A practice employed in the southern U.S. -- where sweet potatoes
are adapted since they love hot weather -- is rotating sweet potatoes
vines into the vegetable sequence to control nutsedge on
commercial vegetable farms; thus a cultural practice is used to
control a noxious perennial weed. The vines of sweep potatoes
are vigorous and thereby function as a smother crop. Yet, in
addition, sweet potatoes are known to release allelochemicals
which specifically reduces nutsedge through an allelopathic
effect.