Can Ground Cover Choke Out Other Plants?

Growth

• Although most ground covers take two or three years to become established, they spread quickly once they get going. Ground covers spread both by underground stolons and by seed to form a dense mat, capable of crowding out weeds and delicate plants.

Varieties

• How well a ground cover crowds out other plants depends on the cultivar. Some, such as English ivy (Hedera helix) and periwinkle (Vinca minor), grow quickly and have sturdy, dense vegetation that crowds out both weeds and perennials. These ground covers can become invasive, spreading throughout your garden or even escaping into the wild. English ivy grows in U.S. Department of Agriculture plant hardiness zones 5 through 11, while periwinkle is hardy in USDA zones 4 through 9. Others, such as spotted dead nettle (Lamium maculatum), which thrives in USDA zones 5 through 8, have more delicate leaves and a slower growing style. These ground covers can crowd out most weeds, but they're not likely to engulf established perennials.

Growing Conditions

• How vigorously plants grow depends mostly on their growing conditions. Under ideal conditions, ground covers can become invasive, crowding out all plants. English ivy is a good example. In moist, mild climates, such as the Pacific Northwest, it has become a real problem, because it grows so vigorously there. In dry areas with cold winters, it rarely becomes invasive. If you want ground covers to crowd out weeds, be sure to select varieties adapted to your region, and plant them in the conditions that suit them best. Many ground covers thrive in shade to deep shade and moist soil, while others tolerate full sun and dry conditions.

Managing Ground Covers

• Ground covers can be a beautiful addition to any home landscape, but they're not maintenance-free. Weeds, especially grasses, can penetrate them and are difficult to remove once established. To keep your ground covers looking their best, walk through them weekly, pulling up any weeds that you see. Cut back ground covers with a weed trimmer or shears midseason if they start growing out of bounds or look shaggy. Plant ground covers with strong, vigorous perennials that can hold their own, and cut back ground covers if they encroach on other desired plants. Landscape fabrics are often installed under ground covers, but they might slow ground covers' growth more than you'd like. They also become worn over time and can allow weed growth. Gravel or wood chip mulches are a better choice.