Spiraea prunifolia 'Plena', as I recall, has graced nearly ever home garden I remember. A curiosity in my youth, the first time I saw its peculiar form was in the garden of our family's second home in the Bay Area. Shaded by the house, Fraxinus veluntina 'Modesto' (Modesto ash), and a full blanket of Clytostoma callistegioides (violet trumpet vine), bridal wreath (as I had known it) acted like a vine, reaching for sunlight with gently weaving limbs. I clipped away whatever competed so it could enjoy more sun, and it returned its gratitude with these delicate blooms. As a cut flower, they last quite some time, however they drop countless petals.
Several gardens later, the plant now receives full sun and is dense. The branches reach for the sky, briefly, before arching and cascading back to the ground. This particular plant has been blooming for nearly a month and does not seem interested in stopping.
Botanical Name: Spiraea prunifolia 'Plena'
Common Name: Bridal wreath spiraea; shoe button spiraea
Sunset Zones: A2, A3, 2-11, 14-21
Plant Type: Deciduous shrub
Optimal Height and Spread: 7' x 7'
Exposure: Full sun to light shade
Primary Feature: Profuse petite white blooms in spring, possibly longer