Problem: Leaf Scorch
Leaf scorch is a condition that may develop in lilies when they are growing in acid soil with a pH lower than 6.5. Toxic amounts of aluminum and manganese salts become available and are absorbed by plant roots in acid soils. Leaf scorch is most likely to occur when the plant is not receiving adequate or balanced supplies of nutrients, such as nitrogen and calcium. During the rapid part of the growing season, significant temperature changes can also cause leaf scorch.
Add ground dolomitic limestone to the soil to decrease its acidity.