Late, Large-flowered Clematis
Clematis 'Jackmanii Superba'

Family: Ranunculaceae (ra-nun-kew-LAY-see-ee) (Info)
Genus: Clematis (KLEM-uh-tiss) (Info)
Cultivar: Jackmanii Superba
Hybridized by Cripps
Registered or introduced: 1878
Synonym:Clematis jackmanii superba
» View all varieties of Clematis

Group:

Viticella

Height:

10-12 ft. (3-3.6 m)

Spacing:

4-6 ft. (1.2-1.8 m)

Hardiness:

USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Bloom Color:

Purple

Maroon (Purple-Brown)

Flower Fragrance:

No fragrance

Bloom Shape:

Single

Bloom Diameter:

Medium - 2 to 5 inches (5 to 12 cm)

Bloom Time:

Mid Spring

Late Spring/Early Summer

Mid Summer

Late Summer/Early Fall

Mid Fall

Late Fall/Early Winter

Sun Exposure:

Sun to Partial Shade

Other details:

Average Water Needs; Water regularly; do not overwater

Danger:

All parts of plant are poisonous if ingested

Handling plant may cause skin irritation or allergic reaction

Pruning Groups:

Group 3 - Summer/Fall bloomers; prune hard in early spring

Patent Information:

Non-patented

Propagation Methods:

From softwood cuttings

From semi-hardwood cuttings

Seed Collecting:

N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed

Regional

This plant has been said to grow in the following regions:

,

Salem, Alabama

Juneau, Alaska

Clayton, California

Denver, Colorado

Newark, Delaware

Rincon, Georgia

Hampton, Illinois

Streamwood, Illinois

Dracut, Massachusetts

West Roxbury, Massachusetts

Trenton, Michigan

Saint Louis, Missouri

Edmond, Oklahoma

Albany, Oregon

Portland, Oregon

Allentown, Pennsylvania

Columbia, South Carolina

Aberdeen, South Dakota

Murfreesboro, Tennessee

Garland, Texas

Rockport, Texas

Fancy Gap, Virginia

Yakima, Washington

Onalaska, Wisconsin

Owen, Wisconsin

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Gardeners' Notes:

3
positives
0
neutrals
0
negatives
RatingContent
Positive

On Aug 15, 2006, northgrass from West Chazy, NY (Zone 4b) wrote:

I love the growing habit of this clematis, never clumps up in masses of tangled stems; it rambles nicely up the porch railing. It also blooms for at least 2 months, maybe more if I would cut out the seed heads. I would love to find a light colored clematis with the same characteristics as this one, so far I have not.

Positive

On May 18, 2005, Gindee77 from Hampton, IL (Zone 5a) wrote:

My favorite clematis so far. I've had the same Jackmanii for over 30 years and it's as beautiful as ever. It does best when you cut it back to the ground in my zone in late March or early April.

Positive

On Apr 15, 2005, Happenstance from Northern California, CA wrote:

Limited success in 10a, trying to find a spot for cool roots and still enough sun has been a challenge. Third season and I'm seeing more buds than in the first two seasons.