Boxwoods have been an important part of North Carolina landscapes since colonial times. There are many types and cultivars to choose from.
While boxwoods will grow in full sun, they prefer a partially shaded location. Fertile soil is not essential but it should be limed to a pH of 6.5 to 7.0. Avoid windy sites such as a corners of buildings or crest of hills. Winter sun and wind will cause the foliage to turn yellow-orange or bronze.
A well-drained soil is essential to avoid root diseases. Boxwoods should not be planted near drain spouts or areas that tend to stay wet. The planting hole should be at least twice as wide but only as deep as the root ball. The plant should be set at the same depth as it grew in the nursery; deep planting can cause an initial loss of plant vigor and possibly plant death. In clay soil it is probably best to prepare a bed to plant in instead of digging individual holes. Raised bed are ideal.
Boxwood are shallow-rooted plant and will suffer during hot, dry weather. Mulching with a 3- to 4-inch layer of pine straw or other organic materials. Mulch will help conserve moisture, reduce weeds, and help keep the roots cool. Check the mulch depth annually and replenish to maintain the desired depth. Excessive mulch is not desirable since the root will tend to grow in the mulch instead of the soil.
Newly planted boxwoods should be watered during hot, dry summer weather until they become established. It may take 2 years in eastern North Carolina. Remember they do not like wet feet.
Ideally, fertilization should be based on a soil test. Many boxwoods are killed by excessive fertilizer applications. For the year you transplant it may be best not to fertilize or to use cotton seed meal. The second year, apply a balanced fertilizer such as 10-10-10 at the rate of 1 1/2 cups per 100 square feet. The best time to fertilize is late fall or early spring before new growth begins. Distribute the fertilizer evenly over the planted area, but not closer than 6 inches from the plant stem. Avoid late summer fertilization, because it can stimulate growth that is more susceptible to cold weather.
Phyophthora root rot is a common disease that seriously injures boxwoods. It is worse in compacted, poorly drained soils such as clay. There is no chemical cure for this disease, but you can take several steps to avoid it. Do not plant boxwoods in poorly drained areas. If you plant them in clay soils, consider planting in raised beds and/or mix a 2- to 3- inch layer of pine bark mulch into the soil before planting.
© Erv Evans, Consumer