A gardener we know calls Spirea the "Grandmother plant" because it takes him back to his childhood and looking at the white blossoms while lazing in his grandmother's front porch swing. Long treasured in the Ozarks, Spirea cantoniensis is gaining new popularity. This variety is called 'Double Bridal Wreath' for its breathtaking double clusters of flowers. It blooms in mid-spring and grows to 4-6 feet tall and as wide.