How Popular Is the Clematis Jackmanii?

Noted Vine

• The ornamental C. jackmanii vine grows to a length of up to 20 feet; you can coax it into climbing a trellis or similar support upon which the plant tendrils clasp and twine. Small gardens benefit from this vine's ability to grow upward along a raised framework. The showy flowers of C. jackmanii burst open into 7-inch blooms that grow in profusion, providing vibrant, long-lasting color.

Cultivars

• The Jackman group of clematis cultivars blooms late in the season -- through July and August and into early autumn. The double, grayish-white flowers of C. jackmanii "Alba" sometimes blossom with a bluish tinge around the sepal edges. "Rubra" bears double, reddish-purple blossoms, and "Superba" yields deep-violet flowers. "Comtesse de Bouchard" produces circular-shaped, rosy-pink blooms touched with a lilac hue.

Uses

• Arbors, fences and rock walls provide ideal supports for displaying the brightly colored Jackman clematis flowers as they bloom along the vine. Garden enthusiasts sometimes cultivate this plant at the foot of a rose bush, where it climbs upward through the shrub's branches and then blossoms among the roses. The large, cut blossoms of C. jackmanii create an elegant centerpiece when floated on the water's surface inside an attractive bowl.

Pests and Diseases

• Root crown borers are common enemies of the clematis plant, infesting various parts of the vine and causing serious damage. Carefully remove affected areas and destroy them. Infestation by root knot nematodes can lead to total destruction of a clematis vine. You must dig the entire plant up, completely eradicate it, and never plant the spot with the same variety of plant. A fungal disease known as "wilt" can have a devastating effect on clematis. Just as the buds become ready to blossom, the plant's stem collapses. During the ensuing days, the stem, along with the foliage, turns black; lesions may develop below the wilted leaves. The entire vine, even that which is just beneath the soil, may exhibit signs of infection. Complete removal of the portion of diseased stem is essential in order to treat this affliction. A bacterial disease called crown gall causes tumorlike growths on clematis; total elimination of the plant, along with its roots, is crucial.