Toni, good thing Long Island doesn't get temperature swings like that. My poor garden couldn't deal with it!
Steve, I am a very, very big believer in mulch. Mulch keeps the soil cooler in the hot summer weather and keeps the moisture in the soil. It breaks down and therefore eventually feeds the soil. Earthworms only help. I have earthworms everywere here in my garden. Not only in my rose beds but all over the garden as just about everything is heavily mulched.