A Few Facts About The American Boxwood
The American boxwood is one of the more popular species of boxwood found in this country, the other being the English boxwood. There are a number of cultivars of both species, usually designed to meet specific climatic or growing zone conditions. In addition to the American boxwood and English boxwood, there are roughly 150 different species of this plant around the world.
Description - The American boxwood, Buxus sempervirens, L. is hardy to USDA Zone 5. The English boxwood, exhibiting similar hardiness characteristics, and being a dwarf, is considered to be the most popular of all boxwood types grown in this country. Boxwoods were introduced to the United States from Europe in the mid 17th and early 18th centuries. The American boxwood is a small shrub, growing to a height of between 5 and 10 feet. The shrub has very dense foliage, with the upper leaves being a very dark and shiny green, while the lower leaf surfaces are a much lighter green. Boxwoods do produce blooms, usually white, but they are small to the point of being inconspicuous.
Culture - Boxwoods usually do best when grown in partial shade. They will grow in most any soil, although the soil should have a pH of 6.5 or higher for healthy plants. The soil, while not having to be especially fertile, should be well drained, as these plants do not take well to standing in water for protracted periods. An important consideration when planting boxwoods, including the American boxwood, is that the plant is susceptible to winter wind damage, which can result in the bronzing of the otherwise evergreen foliage. It's also a good idea to mulch boxwoods, as they are shallow rooted plants, and are not very drought tolerant. Boxwoods usually respond well to fertilizing during the late winter or early spring, just as new growth is starting, Fertilizing in the summer or fall is not recommended, as the new growth may not harden in time to prevent damage from fall frosts.
Pests And Problems - Besides winter winds, frequent frosts and even the winter sun can cause bronzing of the foliage, and a wind break or screen may be needed in some locations. Drought conditions can also contribute to bronzing of the foliage, especially during the winter months. The two most common pests affecting the American boxwood are leaf miners and the boxwood psyllids. An application of an insecticide usually takes care of these two pests. The extent to which either of these pests may be present depends greatly on the location and climatic conditions in which the boxwood is growing. Spider mites can also cause damage to boxwood plants, as can phytophthora parasitica, a fungus present in the soil of some parts of the country, and is responsible for root rot. This fungus is normally not a problem when the soil in which the boxwood is growing is well drained.
Pruning Boxwoods - If anything typifies the care and maintenance of the American boxwood, it is pruning. Pruning may be done simply to remove dead or diseased branches, or to keep the plant from developing a scraggly appearance. Pruning is most often done however to shape a boxwood plant. Sometimes, outer branches need to be pruned back slightly to allow light to enter deeper into the plant, and maintain the denseness of the foliage. Severe pruning of the American boxwood is generally not recommended. The plant will respond, but slowly, as it is a slow growing plant and recovery may take several years if the pruning has been severe enough.
Propagation Is Easy - The American boxwood can be propagated either by cuttings or by layering. Stem cuttings can be taken any time from mid-summer well into late fall, and even into December. Cuttings should be taken from year-old wood for propagation to be successful, and the use of a rooting hormone is recommended. Layering can be an even more simple process. A branch contacting the ground will often develop roots. The rooted portion of the branch can be cut off, the result being a new boxwood plant. Layered plants tend initially to be much more rapid growing than are plants produced from cuttings. Whichever approach is taken, and trying both ways is certainly a thought, propagating the American boxwood can be a pleasant and rewarding task.