This week much of California is under a heat advisory or excessive heat warning, with high temperatures estimated to range from 90 to 108 degrees. Many home gardeners are wondering how they can help their plants, trees or shrubs survive the intense summer heat. “We are getting a lot of inquiries around the state from people worried about how the extreme temperatures are going to affect the plants or trees in their yards,” said Missy Gable, director of the UC Master Gardener......