Which Plants Kill Weeds?

Weeds can get to be a problem when they begin to compete with more desirable plants for such resources as sunlight, nutrients and water. One way to minimize the growth of weeds is to landscape with plants that have the ability to kill weeds. Many ground cover plants can quickly grow to fill in an area, killing any weeds by denying them food and light.

Snow-in-summer (Cerastium tomentosum) is a fast-growing herbaceous perennial that grows best in USDA hardiness zones 3 through 7. In most climates snow-in-summer is evergreen, and its rapid rate of growth gives it an advantage over any weeds that might try to compete with it. Plant it in dry, sunny areas with good drainage. For best results till the soil and remove all existing weeds before planting. Once snow-in-summer is established it will quickly grow to about a foot in diameter. Plant several plants about 9 inches apart to create a dense mat that weeds will not be able to penetrate. Any weeds that manage to get started will be choked out by the snow-in-summer, and the weeds will quickly die.

The barren strawberry (Waldsteinia fragarioides) is a low-growing ground cover -- about 6 inches high -- that spreads rapidly throughout an area, with each plant spreading to cover an area about one foot across, though an individual plant may be smaller than that. This herbaceous perennial reproduces by putting out runners and suckers and will quickly fill an area with a dense mat of dark green leaves. It does best in relatively cool climates and is hardy in USDA zones 4 though 7. Once the barren strawberry is established it will kill any sprouting weeds by denying them sunlight and nutrients. Weeds should be removed from the area before planting this ground cover, to give it a good start.

Japanese pachysandra (Pachysandra terminalis) grows best in partial to full shade when planted in organically rich soil. The dark green leaves on this plant form in clusters around individual stems, creating a shrub-like appearance. Pachysandra establishes itself quickly and forms colonies by sending our rhizomes that create new plants. It is particularly effective at choking out weeds in areas where other ground cover plants have trouble getting established, such as under trees or near buildings. Till the soil and remove all weeds before planting Japanese pachysandra. As this plant begins to colonize, it will kill any weeds that attempt to sprout in the area, because the weeds will not be able to get sun, food or water.