Blue Mist Spirea (Caryopteris clandonensis), will add a heavenly hue of blue to your garden, from late summer through fall. Sometimes known as Bluebeard, Blue Mist Spirea has a profusion of tiny blue flowers that are attractive to butterflies. Caryopteris is long-blooming and has fragrant foliage that deters deer and rabbits. Plant this deciduous shrub alone or en mass as a backdrop for lower-growing perennials or as a hedge.