Blue comes in many forms in the garden, adding calm, cool elegance wherever it blooms. Wee clusters of grape hyacinth have inverted blue bells, with just a touch of lacy white edging. Watery blue iris makes you pause and appreciate. Forget-me-nots and bugloss (Brunnera) add their sprinkling of blue sparkle. And bugleweed (Ajuga) serves up mini spires of frothy, fluffy blue over its green-bronze carpet.