Famed for their durability, beauty, and diversity, hydrangeas are enjoying a renaissance in today's gardens. These classic garden shrubs provide bold color -- from pink to purple, blue to white -- in midsummer to midautumn, when few other plants are in bloom. Many hundreds of dramatic species, hybrids, and horticultural selections are available to the enthusiast to fill every possible niche in the garden. For the first time, a thorough encyclopedia...