Oakleaf Hydrangea Death in Wet Sites: Phytophthora Root Rot

Oakleaf hydrangea hates soggy soil. Wilting from top down over weeks in a wet spot suggests phytophthora root rot. Fix: mix a bag of soil conditioner into each planting hole to improve drainage and raise the root zone. Water only when leaves droop. Each January, remove fallen leaves from the base to reduce disease pressure.