Phytophthora Blight and Dieback

Phytophthora causes blighting and dieback of shoots and foliage, particularly on stressed plants in wet conditions. This pathogen persists in soil and spreads through water splash and root contact. Avoid planting in poorly drained areas. Remove infected material promptly. Improve air circulation through selective pruning and spacing. This blight is most damaging during cool, wet springs when flower and shoot development is rapid. Monitor plants closely during vulnerable periods.

Use many different tactics to manage these diseases but development of an appropriate water management plan is the best cultural practice. Propagate cuttings only from plants known to be free of disease for several months.