. These multi-branched upright shrubs are fast growers. In spring Diablo ninebark bears white or pinkish-white flowers that grow in clusters. The purplish foliage of Diablo ninebark plants (with a touch of red here and there) earn them the nickname “purple ninebarks” or purple-leafed ninebarks.” An increase in red color and a hint of bronze added to the purple in the leaves make them even more attractive in fall. Mature branches exhibit exfoliating bark giving Diablo ninebark plants winter interest.