When is the best time in the spring to visit Charlston

I am planning a trip to your city in the spring. I want to be there when it is warm enough to not need a coat, maybe a sweater or light throw is okey. However, I don't wanty it to be to hot to enjoy walking your beautiful streets. Finally, I am in love with beautiful flowers and want to be sure they are in bloom. I am thinking maybe the last of April or the first of May. I love music and theater, arts and crafts, food and fun. When should I plan to come. If you have a spring festival or fair, that would be nice too.