Building berms allows you to protect your foundation from flooding. These short, rounded earth walls can control the flow of water around your property without ruining the natural look of your landscape. Covering the berms with the right plants helps them blend further into the background while showing off your favorite greenery.
Planting a line of trees across the top of an earthen berm can help them stand out from the rest of the landscape. The University of Minnesota's Sustainable Urban Landscaping program recommends staggering the plantings to create a natural look. The Pacific dogwood (Cornus nuttallii) is a blooming tree that is native to California and hardy in U.S. Department of Agriculture plant hardiness zones 5 through 9. It thrives in the dry soil often found at the top of a berm and has a spreading, open growth habit.
Planting the berm with a hedge of bushy shrubs provides a windbreak and noise barrier. If you don't want to spend a lot of time trimming and maintaining a hedge, consider planting Myrtle boxwood (Paxistima myrsinites). It is native to California and thrives in USDA zones 3 through 9. The evergreen leaves provide screening through the year, and the plant can thrive in conditions ranging from full sun to partial shade.
Since a properly designed berm stays dry at the top most of the time, it provides an ideal location for starting a cacti and succulent garden. The Mojave kingcup cactus (Echinocereus mojavensis) is a California native plant with a mounded growth habit that can cover a lot of soil. It is hardy in USDA zones 5 through 9. Create a focal point in your landscape by adding a few century plants (Agave americana) to the top of the berm. They require full sun and dry soil, and grow in USDA zones 9 through 11.
A mix of native grasses keeps the loose soil on the top and sides of the berm from eroding. The extensive root systems hold the soil. Start with some blue grama (Bouteloua gracilis), a native drought-tolerant grass that grows well in USDA hardiness zones 4 through 9. Include some purple threeawn (Aristida purpurea) to add a touch of reddish color. It thrives in the driest conditions in USDA zones 8 through 10.
- University of Minnesota's Sustainable Urban Landscaping: Building Soil Berms
- Ladybird Johnson Wildflower Center: Native Plant Database -- Cornus Nuttallii
- Keeping It Green Nursery: Cornus Nuttallii
- University of Tennessee Extension Office: Evergreen Trees for Hedges and Screens in the Landscape
- The Wild Garden: Paxistima Myrsinites
- Landscaping Network: Landscaping Earthworks
- Ladybird Johnson Wildflower Center: Native Plant Database -- Echinocereus Mojavensis
- Geoscape Desert Nursery: Cactus Plants
- Royal Crest Nurseries: Agave Americana
- Monrovia: Blonde Ambition Blue Grama Grass
- Joe Raedle/Getty Images News/Getty Images