Disease: winter leaf scorchHost: Rhododendron, cv. Gray Zeppelin
Winter leaf scorch or burn is a common problem of plants that keep their leaves in winter. It is essentially a drought problem. When soils are frozen, water cannot be taken up by the plant, but water continues to transpire from the leaves in the dry air of winter. The leaves of rhododendrons curl up in very cold weather to help reduce this water loss. Leaves typically become dry and necrotic along the edges producing the "scorch" symptom. One way to reduce this kind of injury is to choose sheltered planting sites to reduce exposure to winter winds. There are also sprays that coat the leaves to help reduce water loss.
Image courtesy G.M. Shear from the APS Diseases of Woody Ornamentals and Trees CD-ROM.
Get ALL the Latest Updates for ICPP2018: PLANT HEALTH IN A GLOBAL ECONOMY. Follow APS!