Agronomic Services — News Release

Tips for transplanting trees and shrubs

RALEIGH — Most gardeners find their enthusiasm for gardening with the warming temperatures, longer days and daffodil blooms of late winter. They may not know that fall is also an excellent time to rejuvenate the home landscape, especially for planting new trees and shrubs.

The cost of buying plants and the effort of digging holes and moving plants from pots to garden are good reasons for wanting to do the job well and be successful on the first try.

One of the best ways to start a landscaping project is to collect soil samples from your flower beds. Soil testing is a free service of the N.C. Department of Agriculture and Consumer Services. Soil test reports provide very practical information about soil pH and nutrient levels as well as recommendations for lime and fertilizer, when needed. To find information on how to collect and submit soil samples, visit the NCDA&CS Agronomic Division Web site www.ncagr.com/agronomi or call (919) 733-2655.

Other important factors that affect plant survival and growth after transplanting include site selection, time of planting, method of planting, soil amendments, water and mulch.

Site selection. Evaluate your site and choose plants that are suited for it. Site-specific items to consider include the amount of shade versus sunlight, the moisture level of the soil, and how exposed or protected the site is. It is also important to choose plants that are hardy in this part of the country. Most of North Carolina is in U.S. Department of Agriculture Hardiness Zones 7a and 7b. When you purchase plants at nurseries and garden centers, look for labels that provide information about these environmental needs.

Time of planting. Fall, late winter and early spring are the best times to transplant trees and shrubs. Roots are active during these periods, and weather is less demanding. Summer is generally the most stressful time to transplant trees and shrubs. Good root activity at the time of transplanting is critical because roots provide the food and water essential to successful establishment and growth.

Method of planting. Loosen roots, but do not shake off all of the potting soil. If roots are potbound (that is, growing around in a tight circle), it may be necessary to clip them so they will grow out normally into the soil. Dig the hole two to three times wider than the plant container but not deeper. Position the plant so the crown—the point where the roots and above-ground portion meet—is right at or just above the soil line. Planting a little high is fine since some sinking typically occurs after transplanting. If any stems are damaged in the process, carefully prune them back.

Soil amendments. Some sites need more than lime and fertilizer to be suitable for planting. Many times during new home development, the topsoil is removed leaving heavy, subsurface clay. The physical properties of a heavy-textured clay or even a light-textured sand are improved by the addition of a soil conditioner, such as well-composted organic matter. Soil amendments are best mixed into soil when an entire bed is being prepared for planting as opposed to an individual hole.

Water. Provide adequate water—but not too much—during the establishment phase. A good way to decide whether to add water is to check the moisture of the soil about two to three inches below the surface. If the soil is dry at that depth, water thoroughly in early morning or late afternoon. Once woody plants are well-established, water only during long periods without rain.

Mulch. Finally, after planting and watering, add some mulch. Mulching helps conserve moisture and reduces extreme temperature fluctuations. Three to four inches of mulch is adequate. Don’t get carried away! Too much mulch can weaken the plants in the long run. Also, be sure to keep mulch a couple of inches away from the crown of each plant.

Once trees and shrubs are successfully transplanted according to these guidelines, follow up every two to three years with a soil test. Periodic soil testing is the best way to keep soil fertility and pH within the desired ranges. For advice on collecting soil samples or interpreting your report, contact your local NCDA&CS regional agronomist. Contact information is available online at www.ncagr.com/agronomi/rahome.htm.