The best evergreen ground covers for a slope

Question: We are looking for some ground covers that stay green all winter long. We have a steep slope behind the garage that currently is filled with clumps of daylilies. We like them, but they die back in the winter. We’d like to plant some type of evergreen ground cover in between the daylilies. Do you have any suggestions for good plants?

Answer: I’m assuming that since you’re growing daylilies in the area, it receives a good amount of sun. Thankfully, there are many evergreen ground cover choices that work on sloped areas like yours. Here are a few of my favorites.

• Ajuga reptans — This fully evergreen ground cover is very hardy and comes in a broad range of foliage colors and textures. It hugs the ground at a mere half-inch in height and is covered with spires of purplish-blue flowers in spring. Ajuga, commonly called bugleweed, is a fast, yet controlled, spreader that prefers full to partial shade. I grow a tri-colored variety called “Burgundy Glow” that is a lovely blend of pink, green and white foliage. “Metallica Crispa” is another favorite, with crinkled, dark green/burgundy foliage.

• Iberis sempervirens — Evergreen candytuft has been around a long time. My mom grew it when I was a kid and I have loved it ever since. Smothered in pure white flowers in spring, this plant remains a rich, deep green all winter long. It does not spread via underground roots like some other ground covers, but rather it makes a large, billowing clump and develops roots along the stem as it grows. It is very easy to start from stem cuttings and thrives in full sun.

• Thymus species —Turns out that thyme isn’t just useful in the kitchen. It’s also a great winter-friendly ground cover. With dozens of species and hundreds of cultivars, you can’t go wrong with this lovely little plant. Variegated, wooly, creeping, wild, lemon-scented and English thyme varieties all thrive in hot, sunny areas with well-drained soil. Thyme does best when given a regular haircut, so harvest as much as you want for the kitchen early in the season and then let the plant develop lots of new growth before winter sets in.

• Liriope spicata — The dark green, strap-like leaves of lilyturf remain evergreen through most of the winter, though sometimes mine turn brown around the leaf margins just before spring arrives. Variegated forms are also quite interesting. In spring, spikes of purple-blue flowers poke out of the center. Lilyturf spreads at a moderate rate and is suitable for both full sun and partial shade. If you’d like, you can mow the plants down each spring to encourage new, deep green growth.

• Sedum rupestre — “Angelina” — OK, so this isn’t actually evergreen — it’s ever-yellow. The succulent golden yellow foliage, hugs the ground at a mere 4 inches in height. In spring it bears yellow star-shaped flowers and in the cooler temperatures of fall and winter the foliage turns a beautiful reddish amber color. “Angelina” is drought resistant and tolerant of hot, sunny areas. It is a vigorous grower than can be trimmed back at any time. This plant looks great tumbling over rocks or retaining walls.

There are a handful of low-growing, spreading evergreen shrubs as well, such as wintergreen euonymus (Euonymus fortunei), rug juniper (Juniperus horizontalis), and creeping cotoneaster (Cotoneaster adpressus) that would work in your conditions.