Your home's architecture and landscaping create a dynamic artwork, with foundation shrubs and small trees forging a transition from a geometric structure to natural, living forms and textures. Landscaping next to a house requires special attention to plant roots because certain plants have large, water-seeking roots near the ground surface, and those plants should be avoided. Water-seeking roots can invade a house's foundation and hardscapes, causing those structures to crack.
Besides consideration for plants' roots, plants' requirements for sunlight and moisture as well as U.S. Department of Agriculture (USDA) plant hardiness zones must be met for the foundation plants' success. North Carolina has diverse topography and climate zones, with mountains and piedmont in the west and coast or coastal plains in the east. From the mountains to the coast, USDA plant hardiness zones range from 6a in the state's westernmost regions to 8a along the Atlantic Coast.
Shallow, fibrous-root plants are non-invasive and can be planted next to a house as long as the plants' other cultural requirements are met. Shrubs and small trees with shallow roots require regular irrigation when they are in well-drained soil. Waterlogging drowns shallow roots because they tend to be compact and very near the soil surface.
Small trees with shallow roots add vertical interest when they are used as corner plantings, softening house edges and drawing the eye to explore the landscape. Deciduous trees that grow well in acidic to neutral soil in North Carolina include flowering trees such as dogwood (Cornus florida), which is hardy in USDA zones 5 through 9, redbud (Cercis canadensis), hardy in zones 3 through 9, and star magnolia (Magnolia stellata), hardy in zones 4 through 9. Non-flowering Japanese maple (Acer palmatum) grows in acidic to alkaline soil and is hardy in USDA zones 6 through 8. Plant these understory trees in sites that receive partial sun to partial shade.
Broad-Leaf Evergreen Shrubs
North Carolina climates support a wide range of broad-leaf evergreen shrubs with shallow roots. Kurume azaleas (Rhododendron spp.), hardy in USDA zones 7 through 9, hollies (Ilex spp.), hardy in zones 5 through 9, boxwoods (Buxus spp.), hardy in zones 6 through 9, and barberries (Berberis thunbergii), hardy in zones 4 through 8, are available with different colored flowers or berries, leaf colors, textures and sizes.
Camellias (Camellia sasanqua spp. and japonica spp.), which are hardy in USDA zones 7 through 9, are generally heavy bloomers, producing blossoms in colors ranging from white to red and bicolor. Their bloom periods vary from fall to spring. Gardenias (Gardenia jasminoides), hardy in USDA zones 7 through 10, bloom heavily with white, fragrant blossoms in late spring and throughout the growing season.
Avoid a 2-D landscape design by planting "green growies" -- solid blocks of green -- for height, advised David Goforth in "Conifers for the Landscape," which he wrote for North Carolina Cooperative Extension. Needled evergreens and other conifers with shallow roots add texture and green coloring next to a house. Goforth recommended arborvitaes (Thuja spp.), hardy in USDA zones 3 through 9, and junipers (Juniperus spp.), hardy in USDA zones 3 through 7, as low-maintenance, relatively pest-free shrubs or small trees.
- North Carolina State University: USDA Hardiness Zones in North Carolina
- Virginia Cooperative Extension: Shrubs -- Functions, Planting and Maintenance
- Fine Gardening: Buxus Sempervirens "Green Mountain" (Boxwood)
- Clemson Cooperative Extension: Foundation Plantings
- Arizona Cooperative Extension, Arizona Master Gardener Manual: Botany -- Plant Parts and Functions
- North Carolina Cooperative Extension Service: Residential Landscaping
- The New Sunset Western Garden Book; Kathleen Norris Brenzel, Editor
- North Carolina Cooperative Extension: Conifers for the Landscape
- Photo Credit Comstock/Comstock/Getty Images