Xeriscape Trees & Shrubs

Maureen McCracken

he motto, “right plant, right place” is good for any garden. However, it is a critical rule for a successful Xeriscape. How then do you determine the right plant in a Xeriscape?

The right plant must be a healthy plant, adapted to the extremes of the Piedmont: hot, humid as well as hot, dry summers; and cool, wet as well as cool, dry winters. Ensure the plant is suited to the soil conditions. Once the right plant is identified, encourage the growth of deep roots by preparing/amending the soil, mulching and using appropriate irrigation to help the plant get established. Most Xeriscape plants become drought-tolerant only once they are well established. To find the right place, it is important to identify mini microclimates within the landscape. It is possible to have several mini microclimates even within relatively small yards, as they are created by variations in physical and environmental conditions. Moisture, sun, shade, air movement, heat and structures all contribute to the creation of mini microclimates in the landscape that have different water requirements. Grouping plants with similar water-use requirements is one important criterion for a successful Xeriscape. A grouping of drought-tolerant plants, once well established, may not need irrigation at all through a normal summer. However, adding just one plant with high water requirements to that grouping will eliminate the drought-tolerant benefits. The following descriptions will help identify water-use zones for mini microclimates in the landscape: Very Low Water-Use Zones: Protected shade areas inhibit evaporation. They are also very low water-use zones. In these areas, irrigation is needed only to establish new plants. These areas offer the greatest potential for water saving. Such shaded areas not only reduce water demand, they can also lower indoor temperatures and reduce summer cooling bills. Low Water-Use Zones: Low water zones are somewhat exposed areas that must be watered occasionally to keep plants flourishing during dry summer months. However, water can be conserved significantly by choosing drought tolerant plants, mulching and amending the soil. This will keep irrigation requirements to a minimum and almost eliminated for well-established plants. Most Xeriscape plants will fall into this category. Moderate Water-Use Zones: Moderate water zones are exposed areas with turf or plants with higher water requirements. This zone should be kept small and should be limited to focal points, such as entrance areas and functional areas such as lawns. The following list provides some ideas for trees and shrubs that work well in a Xeriscape, located in the tough and variable conditions of the Piedmont of North Carolina. SHRUBS FOR SUN Common Smokebush, Cotinus coggygria A deciduous shrub, growing 10-15 feet. The bloom provides a colorful and unusual texture. It is a good specimen plant. Scotch Broom, Cytisus scoparius A deciduous shrub, growing 5-6 feet. It has an interesting stem shape and bright yellow flowers in early summer. Forsythia, Forsythia intermedia A deciduous shrub, growing 3-8 feet. Excellent yellow flowers in early spring. Witch Hazel, Hamamelis virginiana A deciduous shrub, growing 5-8 feet. Aromatic with good winter interest.

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Rose of Sharon, Hibiscus syriacus A deciduous shrub, growing 8-12 feet. Beautiful summer flowers in pink, blue and purple. Holly, Ilex An evergreen shrub. Many cultivars, forms and sizes from which to choose. Sun to shade, height up to 25 feet, depending upon the variety. Good hedge and foundation-type planting. Creeping Juniper, Juniperus horizontalis An evergreen shrub, growing 1-2 feet. Useful on slopes. Many cultivars available. Common Juniper, Juniperus communis An evergreen shrub, growing 5-10 feet. Many uses: foundation, screen or hedge. Southern Wax Myrtle, Myrica cerifera An evergreen shrub, growing to 8-15 feet. Excellent hedge or screen. Can be small tree. Will also thrive in partial shade. Nandina, Nandina domestica An evergreen shrub, growing 3-5 feet. Beautiful berries in winter. Good near buildings. Photinia, Photinia fraseri An evergreen shrub, growing 8-15 feet. Excellent hedge material, which is very popular in urban areas. Indian Hawthorn, Raphiolepis umbellata An evergreen shrub, growing 4-6 feet. Adam‟s Needle, Yucca filamentosa An evergreen shrub, growing 3-6 feet. Coarse needle-shaped foliage and white bell shaped flowers on a tall flower spike. Interesting specimen plant. SHRUBS FOR PARTIAL SHADE Abelia, Abelia grandiflora An evergreen shrub, growing 4-6 feet. Sun to Partial Shade. Excellent plant for hedges or slopes with attractive flowers. Butterfly Bush, Buddleia davidii A deciduous shrub, growing 10-15 feet. Sun to Shade. Numerous cultivars available. Great butterfly attractor. Common Flowering Quince, Chaenomeles speciosa A deciduous shrub, growing 6-10 feet. Sun to Partial Shade. Good early spring flowering shrub. SHRUBS FOR SHADE Japanese Aucuba, Aucuba japonica An evergreen shrub, growing 6-10 feet. Often used near buildings on north or shaded side. Gray Dogwood, Cornus racemosa A deciduous shrub or small tree, growing 10-15 feet. Shade or Sun. Good Dogwood for dry soils. Winter Jasmine, Jasminum nudiflorum An evergreen shrub, growing 3-4 feet. Sun or Shade. Will grow much taller if trellised. No serious pests. TREES FOR SUN

Red Maple, Acer rubrum A deciduous tree, growing 45 feet. Excellent tree for any medium-large space. Bradford Pear, Pyrus calleryana, „Bradford‟ A deciduous tree, growing 35-50 feet. Fast-growing early-blooming medium-sized tree. Washington Hawthorn, Crataegus phaenopyrum A deciduous tree, growing 25-30 feet. Excellent specimen plant with beautiful fruit. Turkish Filbert, Corylus colurna A deciduous tree, growing 40-50 feet. Thrives in adverse conditions. Nellie R. Steven‟s Holly, Ilex ‘Nellie R. Stevens‟ An evergreen shrub, growing 15-25 feet. Excellent screening plant. Crape Myrtle, Lagerstroemia indica A deciduous tree, growing 15-20 feet. A favorite multi-stem summer flowering small tree. Numerous cultivars available. Southern Magnolia, Magnolia grandiflora An evergreen shrub, growing 60-70 feet. A favorite evergreen that needs plenty of room. Wonderful fragrant flowers. Black Locust, Robinia pseudoacacia A deciduous tree, growing 30'-50 feet. Survives in worst locations and conditions. Several varieties available. TREES FOR PARTIAL SHADE River Birch, Betula nigra A deciduous tree, growing 25-40 feet. Multiple stems. Quite popular. Interesting bark in winter. Eastern Redbud, Cercis canadensis A deciduous tree, growing 20-30 feet. Beautiful flowers in spring. Many cultivars available. TREES FOR SHADE American Hornbeam or Ironwood, Carpinus caroliniana A deciduous tree, growing 20-30 feet. Heavy shade. Performs best in shaded areas. Carolina Cherry Laurel, Prunus caroliniana An evergreen shrub, growing 20-30 feet. Attractive white flowers. Good medium-sized evergreen tree for shaded spaces. MM ______________ An Extension Master Gardener Volunteer with Mecklenburg County, NC, since 2006, Maureen McCracken is an avid gardener. She is also a Master Composter with the county. Maureen credits her love of flowers and horticulture to her grandmother, who loved all plants and maintained a multi-use cottage garden with flowers, shrubs, fruits and vegetables.