A guide to caring for groundcovers on slopes

It's frustrating to cultivate the erosion-prone soil on a slope. Taking a gentle approach is the best idea. Here's a simple guide to planting on slopes:

• Clean away existing vegetation by hand or smother it by covering the soil with black- or clear-plastic sheeting for two or three months, a process called solarization.
• If you cannot take the time to weed or solarize, kill the vegetation with a commercial herbicide, following label directions carefully.
• If there is insufficient topsoil on your hillside to plant in, you should spread as much good topsoil on it as necessary to form a smooth planting bed.
• Immediately plug in new plants, firm them in well and apply a thick layer of straw mulch on the soil around the new plants.
• Straw is less likely to blow or wash away than other mulches and it reduces evaporation while the plants are extending their roots.
• Irrigate as often as needed to keep the soil lightly moist for at least a month, or until the plants show signs of new growth.
• How do you know when a plant is established? New growth above ground usually reflects the development of strong roots below the soil.
• If you are in doubt, you can gently tug on the stems. A plant that is established resists being pulled out of the ground.

• Two ground covers that are often used as lawn alternatives can also be used to cover slopes.
• In sun or partial shade, Japanese spurge will form a solid carpet, choking out weeds.
• Small spikes of white flowers appear in early summer.
• On shady slopes, periwinkle can achieve similar results. This has blue or mauve flowers in spring.

• Although mulch deters many weeds, a few always manage to gain a foothold.
• Weed plantings as often as needed for the first two seasons.
• After the first season, consider using an herbicide to control weeds, but read the label carefully to make sure the product is safe to use around ground covers.
• After the second season, the plants should spread into a carpet that few weeds penetrate. Maintenance is easy.
• In spring, use a balanced, controlled-release fertilizer, remove debris and renew gaps in the mulch. In time, the plants will weave into a community that is naturally care-free.

• Gardening on slopes isn't easy, so plan to do it as seldom as possible.
• It's wise to use long-lived ground cover plants that get bigger and better with time, such as creeping juniper.
• As the juniper spreads, it will cover space initially occupied by perennials.
• This long-lived, drought-tolerant, densely growing shrub never needs trimming, making the slope easier to maintain.

Although it's a bit of work, planting groundcovers on slopes can be a very rewarding experience, if you have the patience. As well, it will definitely cut down on the time and effort you have to spend maintaining and mowing sloped areas. If you're in it for the long-haul, get out there and start planting!