- The vines are available as the popular large-flowered hybrids as well as small-flowered hybrids and species. They are typically planted to grow up a lamppost or trellis, but are also attractive when allowed to clamber up a tree or shrub.
- Shrubby clematis are commonly used in the perennial garden, where they offer late-season color. Most have a rather lazy habit, and can be supported using neighboring plants or stakes and twine.
- Trailing clematis are the least known, and are typically either tied to a support such as a mailbox or a lamppost, or given the chance to trail freely through a garden.
Clematis are generally easy to grow, providing that certain conditions are met. First, they usually require at least 1/2 day of sun. Afternoon shade will benefit the blossoms of many clematis, especially those with prominent contrasting “bars” in the flowers. A deep, fertile soil is also needed, which can be prepared by digging a hole at least the size of a 5-gallon bucket, and discarding any poor soil. To the better soil, add an equal quantity of organic matter, such as Coast of Maine™ compost. One-half cup or so each of ground limestone and an organic fertilizer such as Pro-Gro™ is also beneficial. Blend all the ingredients, dump the amended soil back into the hole, and plant the clematis carefully, taking care not to damage brittle stems when securing to a trellis or other support. Good mulch helps to keep the soil cool and moist. Water well, and maintain it as you would any new planting.
Large-flowered clematis are susceptible to a disease known as Clematis Wilt. This disease remains a mystery to gardeners and scientists alike, for it is unknown if it is caused by a fungus, wounding of the stems caused by windy conditions or mishandling, or a phenomenon of the plant being unable to provide enough water to the stems during stressful weather. In any event, it is characterized by a sudden wilting of the leaves starting at the tips of the stems, and progressing downward. Benomyl™, a commercial fungicide, is commonly used to counteract it. Pruning the stems down to healthy growth will often stop the disease, and new stems will usually arise from buds hidden below ground. Clematis Wilt rarely, if ever, will kill clematis; at most flowering may be disappointingly delayed. Please note that The Mixed Border Nursery will not replace any clematis that has been affected by Clematis Wilt.
Pruning clematis is often confusing to the uninitiated. However, once you understand that you will not kill clematis either by pruning it according to the wrong method, or by not pruning it at all, it becomes much easier. Clematis are grouped according to the way they flower, and this governs how they ought to be pruned. If you are unsure what type you have in your garden, observe its flowering habits for a season, and follow the recommendations that most closely match what you have. Except for Group 1 types, all may be cut back severely in spring with at worst a temporary effect on flowering.
Group 1:
These plants flower early on old stems and generally do not need to be pruned, except to remove dead or damaged stems. If pruning is necessary to control growth, cut stems back after flowering.
Examples:
Clematis alpina and varieties
Clematis macrophylla and varieties
Group 2:
These also flower on old wood, but a later flush of flowers happens in late summer on new growth. In early spring before buds have opened, prune out any dead or weak stems, and cut back remaining stems to a pair of buds. The lower down the stems you cut, the more flowering will be delayed. Cutting the stems by half is a good rule of thumb.
Examples:
| Clematis ‘Amethyst Beauty’ | C. ‘Arctic Queen’ | C. ‘Asao’ |
| C. ‘Bee’s Jubilee’ | C. ‘Belle of Woking’ | C. ‘Blue Ravine’ |
| C. ‘Carnaby’ | C. ‘Crystal Fountain’ | C. ‘Diana’s Delight’ |
| C. ‘Duchess of Edinburgh’ | C. ‘Elsa Spath’ | C. ‘Empress’ |
| C. ‘Franziska Maria’ | C. ‘Guernsey Cream’ | C. ‘Henryi’ |
| C. ‘Isago’ | C. ‘Josephine’ | C. lanuginosa ‘Candida’ |
| C. ‘Nelly Moser’ | C. ‘Niobe’*** | C. ‘Perrin’s Pride’ |
| C. ‘Piliu’ | C. ‘Proteus’ | C. ‘Rebecca’ |
| C. Rhapsody’*** | C. ‘Rosemoor’ | C. ‘Silver Moon’ |
| C. ‘Sunset’*** | C. ‘Sugar Candy’ | C. ‘Veronica’s Choice’ |
| C. ‘Vino’ | C. ‘Vyvyan Parnell’ | C. ‘Warsaw Nike’ |
Group 3:
Flowers are produced on new stems each year, so vines can be cut down to a pair of buds near the ground in late winter or early spring.
Examples:
| Clematis ‘Alionushka’ | C. ‘Arabella’ | C. ‘Barbara Harrington’ |
| C. ‘Comtesse de Bouchard’ | C. ‘Hagley Hybrid’ | C. heracleifolia and hybrids: ‘Mrs. Robert Brydon’ |
| C. integrifolia and hybrids | C. ‘Jackmannii Superba’ | C. ‘Niobe’*** |
| C. ‘Perle D’Azur’ | C. ‘Petite Faucon’ | C. recta and varieties |
| C. ‘Rhapsody’*** | C. ‘Roguchi’ | C. ‘Rouge Cardinal’ |
| C. tangutica and varieties | C. ternifolia (aka C. paniculata) | C. texensis ‘Duchess of Albany’, ‘Odoriba’, ‘Pagoda’ |
| C. ‘Ville de Lyon’ | ||
| C. viticella and hybrids: | ||
| C. v. ‘Mrs. Betty Corning’ | C. v. ‘Etoile Violette’ | C. v. ‘Kermesina’ |
| C. v. ‘Polish Spirit’ | C. v. ‘Purpurea Plena Elegans’ | |
***Note: these varieties may be pruned according to either Group 2 or Group 3.
Photos courtesy of Donahues Clematis
