A favorite indoor-outdoor flower adorns the summer in colorful bursts of petals. Perhaps the most abundantly blooming plant, hydrangeas have captivated gardeners and cultivators alike with their old-fashioned charm and tantalizing colors. From late spring to early autumn, they burst from the ends of stems in natural bouquets of vibrant pink, stunning white, lavender, rose, and blue. With over 75 species and 600 named cultivars...