How to Identify problems with heat scorch on roses
John White and Rosemary Maddox address garden problems concerning heat and sun damage on their plants. Rosemary grows tomatoes that grow healthily, but are dry and cracked at the top. John identifies the problem as an excessive exposure to heat and sunlight, and recommends putting a netting over the plants to filter and moderate the sunlight. Rosemary also has a similar problem with her roses. The leaves on her rose plants become yellow and brown and eventually die off. John calls it "heat scorch." Rosemary also shows a Three Leaf Sumac sample that has what John calls "nipple galls" that is caused by insects laying eggs in the plant. This does not actually harm the plant. Rosemary shows a grape vine sample that has a "grape leaf hopper" infestation - tiny insects that suck out the juice and nutrients from the leaves.