But if Phytophthora root rot is confirmed, the site should be avoided for future boxwood plantings. Leaves turn from normal dark green to light green as the plant declines. Roots are dark and rotted. The bark rots and peels at the crown. Death of the entire plant is characteristic of this disease.
Root rot is favored by high soil moisture and warm soil temperatures.
The disease is more severe in heavy clays or poorly drained soils. Over-watering plants or long periods of heavy rain also favor disease development. Phytophthora root rot must be prevented, as chemicals are often ineffective in controlling this disease after above-ground symptoms become obvious. Purchase disease-free plants from a reputable nursery. In areas where plants susceptible to root rot have died, replant with plants that are not susceptible.