Suggestions for groundcover-growing success

With fast-growing perennial groundcovers, take the time to prepare the planting site well, as plants will be living in their new home for many years. Follow these suggestions for groundcover-growing success.

• Dig the soil at least 15 centimetres (six inches) deep and mix in compost or other organic matter to improve the texture
• When setting out slow-growing groundcover shrubs, however, prepare individual planting holes in unimproved soil, because cultivating soil unnecessarily often triggers an explosion of germinating weed seeds
• Make sure you have enough plants, which may be more than you think. Perennial groundcover starter plants are usually planted 15 to 30 centimetres (6 to 12 inches) apart in all directions, and closer spacing results in faster coverage
• When planting a large area or a steep slope with spreading shrubs, it is often wise to stretch a sheet of landscaping fabric over the prepared soil, then cut holes in it where you need to set in the plants
• When finished, top with eight centimetres (three inches) of an ornamental mulch, such as shredded bark or bark chips. Besides suppressing weeds, this "double mulch" retains soil moisture

Sun-loving shrubs that spread into care-free groundcovers include low-growing cultivars of:

• cotoneaster
• euonymus
• juniper
• Russian arborvitae

Shade-loving perennial groundcovers include:

• asarum
• dead nettle
• epimedium
• fern
• hellebore
• lungwort
• periwinkle
• sweet woodruff

Where at least a half day of sun is available, select from among these perennials:

• bugleweed
• dianthus
• lamb's ear
• creeping phlox
• thyme
• spreading veronica

• After planting, irrigate groundcovers as needed to keep the soil moist the first season to help them become established
• While groundcovers are filling in, you can sprinkle a pre-emergent herbicide, which prevents weed seed from sprouting, on the soil around them. It will not harm groundcover plants, as this product only affects seeds. Even so, some hand weeding is usually necessary before plants start to spread
• Pull out weeds when they are young, so that you disturb the soil as little as possible and prevent the weeds from robbing water and nutrients from the groundcover
• After two seasons, the weed population will drop sharply as the groundcovers take over, blocking the light that weeds need to grow

Groundcovers can do a much better job when they are adequately fertilized. In early spring, spread a balanced, commercial, slow-release or organic fertilizer at the rate recommended on the package. You can also spread five centimetres (two inches) of compost or well-rotted manure.

• Tiny, stationary tan or brown discs attached to plant stems are a sign of scale, which is not an unusual insect pest to discover lurking in groundcovers
• Trim back badly infested stems and destroy the clippings
• You can treat moderate outbreaks with commercial dormant oil or a pesticide labeled for use on the plant species with the scale problem. Use according to label directions

Just as grass requires routine mowing, groundcovers may need regular edging and cutting back. Hard edging materials, such as bricks or flat stones, can reduce the frequently of this chore, but you may still need to use pruners, garden shears, or a mower to keep spreading groundcovers from moving into areas where they are not wanted.

If, after a hard winter, your groundcover plants have brown and tattered foliage, you can renew them in early spring by cutting them back nearly to the ground using a string trimmer or mower set at a high setting. Within a few weeks, they will produce fresh, healthy new foliage.

With proper preparation and minimal upkeep, you can enjoy thriving low-maintenance perennial groundcovers for years to come.