Slopes pose a landscaping challenge: The steeper they are, the harder they are to work with. But they also offer an opportunity — a better view. In a flat landscape, a ground cover of lavender and lantana, above, might be lost among taller companions. But on a slope, they’re easier to see and appreciate.
Steep slopes should be covered to prevent erosion. Grass is a great soil stabilizer, but on an incline it can be difficult — and dangerous — to mow. One option is to install terraces that gradually step the grade downward. These stone walls provide multiple levels of flat ground that are easily accessed. The daylilies (first tier) and Russian sage (second tier) are large enough to command attention from a distance yet need no extra watering once established.
Another solution is to plant woody plants, such as these white birch trees shown in fall. Trees have an extensive root system to stabilize soil and an expansive canopy to soften rainfall. Underplant with ferns, hostas, or shade-tolerant ground covers such as vinca vine, which will gradually spread to fill the site. Protect bare spots with a mulch of shredded leaves or wood chips.
Spreading ground covers are great for slopes. The only drawback is that they can take a few years to fill in. Once in place, though, ground covers do a fantastic job of stabilizing the soil with their migrating roots. And they look pretty, too, like this ajuga shown blooming in spring.
Ivy can be an excellent, no-maintenance ground cover. This English ivy (Hedera helix) is in a small, contained area where it won’t cause problems. Avoid using it near woodlands, as it can become a thug. Two other possibilities: Boston ivy (Parthenocissus tricuspidata) and Virginia creeper (Parthenocissus quinquefolia), both offering pleasing red fall color.
If an ivy-covered slope doesn’t hold enough interest, try something more elaborate. This small bank is in a prominent location by some steps, so the homeowners created a natural scene complete with boulders. Easy-going plants include lavender, campanula, agapanthus, society garlic, and pink-flowering bougainvillea at the base of a retaining wall.
By their very nature, slopes drain rapidly. Many are also sun-drenched. Those are two good reasons to use drought-tolerant plants. These heathers are used to growing in the harsh conditions found on hillsides. Aesthetically, they add color when in bloom and texture throughout the growing season.
With the right plants and mulch, a slope can become a featured part of your landscape. Better yet, you’ll be doing your part for the planet by protecting a precious resource: soil.