Red twig dogwood bush
Some of the leaves are turning yellow. What is the cause?
Yellowing leaves could be due to pests, disease or environmental stresses.
Check for marks on the leaves or holes in the leaves.
Leaf scorch can be caused from excess wind in hot weather. This may look like disease but it is not.
Watering is necessary during dry hot spells. Adding a good 3 to 4 inches of hardwood mulch around the shrub will help with moisture retention.