Boxwood Shrubs Turning Brown
Boxwoods (Buxus spp.) have been in cultivation for hundreds of years and are popular for their superior ability to take any shape, given adequate pruning. They are hardy to U.S. Department of Agriculture plant hardiness zones 4 through 8. These low-maintenance, compact shrubs typically feature small green leaves. In some circumstances, boxwoods may turn brown.
Natural Winter Appearance
Some boxwoods, like the Korean boxwood (Buxus sinica var. insularis) naturally go dormant in winter and turn brown as a result. This natural browning can be mitigated somewhat with adequate watering practices in the fall. This is especially important if the rainfall in autumn is low. Water your boxwoods 1 inch per week. Water in winter months as well, but cut watering to once every two weeks.
Some boxwoods turn brown as a result of cold damage. This is particularly rare in the upper USDA zones that boxwoods will grow in. For gardeners growing boxwoods in temperate, coastal areas where frost is uncommon, this is generally not something to be concerned with. However, boxwoods that develop tender new growth late in the season may be vulnerable. Avoid fertilizing or overwatering your boxwood late in the summer to prevent unwanted late-year growth spurts.
Overfertilization may cause the leaves of your boxwood to become scorched at the edges, or entirely brown. Boxwoods have shallow roots and are especially vulnerable to overfertilization. For best results, fertilize only once per year, in early spring. Boxwoods respond well to cottonseed and urea fertilizers, in granular form. Boxwoods protected by a layer of mulch over the soil are less likely to become burned by fertilizer. A deep watering after fertilization will also prevent root burn.
Blight is a fungal disease that causes the leaves of boxwoods to become spotted and then turn brown. This fungal disease causes massive defoliation on infected specimens. There is no known cure for this problem; infected plants and roots must be removed and discarded, not composted. You can avoid this problem by inspecting all boxwood specimens before planting them on your property. Leave sufficient space between boxwood shrubs to allow for generous air circulation to avoid the spread of the disease should one of your plants become infected. Remove all debris from infected plants.
Leslie Rose has been a freelance writer publishing with Demand Studios since 2008. In addition to her work as a writer, she is an accomplished painter and experienced art teacher. She has a Bachelor of Arts degree in art with a minor in English.