Boxwood is an ornamental plant that is well-loved in numerous landscape and park settings. A newly invasive disease, boxwood blight, has spread to most U.S. states and threatens boxwood plants by killing back foliage and causing ugly symptoms of browning, curling, and dieback. The disease can be managed in numerous ways including being aware and ready to prevent its spread when the environmental conditions are favorable. This model predicts the temperature and moisture conditions from nearby weather stations and uses an infection risk index to signal when infections are most likely to occur. With this information, landscape and nursery managers, as well as household owners, may take actions such as using approved fungicides and cultural practices to mitigate infection risk.