The 4-petaled blooms are held wide open and measure 4 inches across. A rich, velvety purple, their color is enhanced by central reddish-purple stripes on each petal and contrasting creamy green anthers.
These blooms arise by the hundred on climbing plants that eventually reach 12 to 20 feet high and 4 to 6 feet wide. Not a plant for the mailbox, this is a Clematis you want to climb a pergola, thread through a trellis, and grow up through shrubs and small trees.
Famously tolerant of a wide range of soils and aspects, Jackmanii is vigorous and robust. Best in light (not deep) shade, such as that provided by the high canopies of tree branches. Pruning Group III.