Jackmanii Superba Clematis

Light Needs

Partial Shade to Full Sun

(At Least 3 Hours of Direct Sunlight)

Mature Height

10-12 Feet

Mature Spread

2-3 Feet

Growing Zones

4 to 8

Clematis Jackmanii is one of the most well known clematis varieties. It was introduced in 1862 and the first late large-flowered hybrid clematis available to gardeners. The violet-purple flowering vine was named after the nurseryman George Jackman. Mr Jackman created the clematis hybrid by crossing it between clematis lanuginosa, clematis viticella, and clematis × hendersonii in 1858.

The dependable and hardy Jackmanii is still grown today as one of the most popular varieties in the United States. Jackmanii Superba Clematis is a newer improved version of the original Jackmanii, and has been bred for more attractive flower petals that are a deeper purple color than the original. The flowers will change from deep purple to a lighter lavender or violet color as the flowers get older.

Jackmanii Superba vs Jackmanii

Jackmanii Superba is considered an improved version over the original. This new plant has more profuse blooms and the flowers are slightly larger as well. We recommend growing the improved Superba variety over the traditional original jackmanii clematis. Or you can grow both for a classic vine mixed with the new and improved version! 

Jackmanii Superba Clematis Care

Caring for purple clematis jackmanii is extremely easy once established. The hardest part is getting the new plants established and the roots growing strong. This plant grows rapidly and does best in full sunlight locations that get at least 6 hours of direct sunlight. Try and choose a location where the “heads in the sun, feet in the shade”. Which means, the plant does best if the vines get direct sunlight, but the base of the plant is protected by some shade throughout the day.

The plants require well draining soil and hate wet feet, which can cause root rot and the plant to die if severe enough. We also recommend adding a layer of mulch at the base of the plant to help protect the roots and retain moisture.

Clematis Jackmanii bloom time goes from early summer and will rebloom throughout the fall until the first frost. In late fall, the flowers change to small, dry seed heads with silky tails.

We recommend providing support for clematis to grow on. It can be left to sprawl as a groundcover, but that is more difficult to do and harder to keep the plant healthy. The plants will grow by twining the leaves on any nearby support like walls, trees, shrubs, mailboxes or fences. The most common support is proving a metal or wooden trellis for the plant to climb on.

Pruning Jackmanii Superba Clematis

Clematis Jackmanii are considered a group 3 clematis, which means the vine blooms on new wood, and the plants can be cut back hard in the late winter or early spring to within 6 inches of the ground. This is a fantastic way to clear out old growth and start fresh every year. The plant can climb up the old growth if you leave it, which can provide additional support if you choose not to trim the plant back.

Fertilizing Jackmanii Superba Clematis

If you choose to fertilize jackmanii, use a balanced slow release fertilizer. Apply in spring, summer and fall if you wish. Keep in mind these plants prefer neutral soil. So an easy alternative to fertilizing is by adding high quality compost around the base each year, which will help maintain a healthy balance of nutrients. You can also get the soil tested if the plant is not looking healthy, to see if what needs to be added to the soil.