How to Help Birds Beat the Heat
Trees and shrubs that grow dense branches obviously provide the deepest shade, and it’s also helpful to grow plants that will together build layers of foliage that birds can enjoy. Vines, longer grasses, and dense groundcovers also build cooler refuges in other parts of the garden. Plants that provide food as well as shade are obviously doubly appealing for birds.
Here are some good resources that share more detailed information about how to help birds out in the summer heat -
The Audubon Society:
The Cornell Lab of Ornithology
By Catherine Griffin
By Susan J. Tweit