Jackman clematis is an especially hardy deciduous climber that produces single, dark, 4-inch purple flowers in early to late summer. Jackman was awarded the RHS First Class Certificate and grows in full to partial sun 10 to 12 feet tall. It is a member of clematis pruning group 3 and flowers on the current year’s new growth. It requires yearly hard pruning down to new buds in late winter or early spring. Grow it on a trellis, obelisk, or pergola, or train it on large shrubs or small trees.