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TREES & plants

Jackman's clematis and the Jackman group of hybrids

Large purple flowers of 'The President', a jackman hybrid.

Jackman's clematis is a very old and well known clematis with large, dark purple flowers.  It is the picture that comes to mind when the word clematis is spoken.  There are a number of hybrids derived from this species and they are known as the Jackman group or the Jackman hybrids.  These hybrids generally have large flowers.

Botanical name: 
Clematis x jackmanii
All Common Names: 
Jackman's clematis
Family (English): 
Buttercup
Family (Botanic): 
Ranunculaceae
Tree or Plant Type: 
  • Vine
Native Locale: 
  • Non-native
Landscape Uses: 
  • Massing, 
  • Screen, 
  • Shade tree, 
  • Specimen
Size Range: 
  • Large plant (more than 24 inches)
Light Exposure: 
  • Full sun (6 hrs direct light daily), 
  • Partial sun/shade (4-6 hrs light daily)
Hardiness Zones: 
  • Zone 4, 
  • Zone 5 (Chicago), 
  • Zone 6, 
  • Zone 7, 
  • Zone 8
Soil Preference: 
  • Alkaline soil, 
  • Moist, well-drained soil
Season of Interest: 
  • Early summer, 
  • Mid summer, 
  • Late summer
Flower Color & Fragrance: 
  • Blue, 
  • Pink, 
  • Purple, 
  • Red
Shape or Form: 
  • Vining
Growth Rate: 
  • Fast
More Information: 

Size and Method of Climbing

Jackman's clematis can grow up to ten feet.  It is a twining vine (and also has petioles that twine).  Twining vines climb by twisting their stems or leaf stalks around a support.  This type of vine grows well on trellises, arbors, wires or chain-link fences.

Plant Care

Full to partial shade.
Mulch to keep roots cool.
Moist well-drained soils.  Tolerate of a wide range of soil pH.
Flowers on new wood, so it should be pruned in winter or early spring. (Pruning will vary on the hybrids as some flower on old wood and some on new wood.)

Disease, pests, and problems

Leaf spots are common among clematis as is stem wilt (wilt being the more serious problem).
Powdery mildew can also occur.

Disease, pest, and problem resistance

Tolerant of black walnut toxicity.

Native geographic location and habitat

Of hybrid origin.

Leaf description

The opposite leaves are pinnately compound.

Flower description

Jackman's clematis has large (4 to 6 inches across), deep purple flowers , with 4 to 6 showy,petal-like sepals.  The Jackman hybrids produce large flowers in a variety of colors (purple, red, pink and blue).

Fruit description

The fruits are groups of achenes, each with a long, plume-like tail.

Cultivars and hybirds and their differences

This is a selection of the Jackman hybrids.  There are other culitvars in the Jackman group and there are other groups of clematis.  Check local nurseries for availability.

Alba  clematis (Clematis x jackmanii 'Alba'):  White flowers.

Comtesse De Bouchaud clematis (Clematis x 'Comtesse De Bouchaud'):  Pink flowers produced in large quantities.

Hagley hybrid clematis (Clematis x 'Hagley Hybrid'): Pink flowers with ruffled edges.

Madame Baron Veillard clematis (Clematis x 'Madame Baron Veillard'): Mauve-pink flowers.

Rubra clematis (Clematis x jackmanii 'Rubra'):  Red-purple flowers.

Star of India clematis (Clematis x 'Star of India'):  Purple flowers with red-purple stripe on each sepal.

Superba clematis (Clematis x jackmanii 'Superba'):  Purple flowers, heavy flowering vine.

The President clematis (Clematis x 'The President'):  Large purple flowers.

Clematis x jackmanii or Jackman's clematis and the Jackman group of hybrids

We do not seem to have this in our living collection.