Clematis jackmanii is one of the easiest of all clematis to grow. It grows 10 to 20 feet tall and puts on a show of 4-inch, dark, violet-purple, abundant flowers in mid-summer. Jackmanii is one of the oldest selections of clematis hybrids, discovered in 1863 by clematis hybridizers George Jackman and his son, George Jackman II. Like all clematis, jackmanii likes to grow in sun or part-shade, in deep soil rich in organic matter. All clematis are classified according to their pruning group — 1, 2 or 3. Jackmanii belongs to pruning group 3, the simplest of all pruning groups.
Cover with 2 inches of finely shredded bark mulch to help keep moisture in and weeds out. Be sure the mulch does not touch the stems.
Jackmanii is pronounced jack-mah-nee-eye.
Prune the plant anytime in winter while it is dormant or in early spring before it has started to emerge. The later in the spring season you prune, the easier it will be to identify healthy buds. Do not prune too late, or energy will be diverted to the upper part of the plant that will be cut down.