Native to Europe and western Asia, this vigorous ground cover has naturalized in much of the South. It spreads by creeping roots and is especially aggressive in rich soil. Confine it behind a concrete, stone, or metal barrier set 812 in. deep into the soil. Light green leaves, each with three leaflets, form a dense mass to 6 in. high; flat-topped clusters of white flowers rise above the foliage in summer. Mowing two or three times a year keeps the planting neat. Remove faded flowers promptly to prevent unwanted seedlings. Clumps of bishop's weed are easy to dig and divide, making it a popular passalong plant.
'Variegatum' is the selection most often planted, with white-edged leaflets that create a luminous effect in shade. Set plants 1 ft. apart for quick cover, and pull up any plants that revert to solid green.