What perennial groundcover can I plant on a sunny slope that is difficult to mow?

A Question of the Week
creeping phlox

For those who want to reduce the amount of turf grass in their garden or have areas that are difficult to mow, a perennial groundcover species may be the perfect choice. Groundcovers are an integral part of any low maintenance landscape. They reduce erosion, lessen weed incursion, require relatively few inputs and don’t require mowing. Groundcovers are particularly useful on slopes, which are prone to unstable soils.

Many gardeners think of groundcovers as low growing, herbaceous, evergreen plants that spread quickly to form thick layers of vegetation. While this certainly describes the typical groundcover such as spurge (Pachysandra) or English ivy, there are many other options. Many other herbaceous perennials and shrubs make great groundcovers. Steep, sunny slopes are perfect for perennials such as daylilies, creeping phlox, lamb’s ears, stonecrop and a variety of ornamental grasses. A number of woody plants can also serve as good groundcovers, especially creeping juniper, fragrant sumac, bearberry, and Russian arborvitae.

Day lilly
Daylily, a great perennial groundcover for steep, sunny slopes

Although groundcovers are generally low maintenance plants, they will still require some care, especially until they become established in the landscape. Until the new ground cover fills in, it can be assumed that weeds will make their way into the garden. Some groundcovers are more prone to weed problems than others. Short, herbaceous ground covers are more likely to become infested with weeds than taller shrubs, because taller plants do a better job of blocking light from reaching the soil.

Lambs ear
Lamb's ear, another perennial that can be used as a groundcover on steep, sunny slopes

It’s also important to note the ways that the groundcover spreads. Be wary of plants that propagate by suckers, stolons, or rhizomes. These perennials often spread quickly outside of their intended borders and sneak into neighboring beds, lawns, or woodland areas. A number of groundcovers can verge on the point of being invasive so do your homework before you plant. Ask UNH Extension for specific ground cover recommendations for your own yard.

Pictured at the top: creeping phlox, a great choice for a perennial groundcover for steep, sunny slopes.

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