Clematis Plants – A Vine And Rose Rival

If any plants can rival the rose for perfection of flower form, royalty in color, and all-round decorative adaptability, count on the clematis.

If anything, these vines have a wider variety of flowers and foliage texture. And in fall and winter the silvery-spidery seed pods are more enticing than red rose pips.

Most clematis are woody perennial vines – evergreen, semievergreen, deciduous, or herbaceous according to type and to climatic conditions. They climb by clever leaf stems that turn and hook like tendrils, to heights from six feet to thirty.

There are clematis for every climate. In areas where peonies and iris flourish, hardiness is no problem. For colder areas there is a selection of herbaceous types that come back from the roots in spring. For very hot climates there are charming evergreen species.

Indoors or out, in container, garden bed, or greenhouse, wherever you want a well-mannered vine that’s exotically colorful yet easy to control and care for – plant one of the large-flowered hybrids. Choose your colors from pink, soft or glowing rose, creamy or pure white, mauve or lavender, striking violet or deep, velvety purple. The saucer-shaped flowers can measure more than six inches across, and many are embellished by intricate stamen formations of contrasting color.

Train one of these huge-flowering beauties on a post or light trellis for a big show in small garden space, or for accent in the large perennial border. Plant one with a climbing rose for more color and a longer season of bloom. Cut a flower for a ten-dollar corsage, or several for a long-lasting flower composition. Use these vines as specimens or aristocratic backgrounds in outdoor container gardens. Grow them indoors in winter around a sunny window, or force them in the greenhouse – even the camellias can’t compare.

Or try the daintier flowering species with blooms like stars, urns, bells, lanterns; in shades of pink, red, gold, cream, or white. Many make dense growth and climb fast to make floriferous shades or screens, camouflage unsightly fences and buildings, scramble over stones and walls, or cover slopes and banks. A combination of early- and late-flowering types will provide continuous bloom from spring through fall.

All gardeners admire and covet the clematis, but too many believe all they hear about cultural difficulties. Select a type suitable for your area, plant it carefully and well, supply its few simple needs, and you can have clematis to revel in for years on end.

Hardiness, planting time, pruning, and training vary with the species and with hybrids of different parentage. It is important to know, when you select a clematis, whether it flowers on last year’s wood – usually in spring or early summer – or on new growth made in the current season, from midsummer into fall. Comb your catalogue or ask your supplier for this important information; or track down the parents of a hybrid.

Species and hybrids that flower on old wood are usually considered less hardy in cold areas than the others that can have top growth winter-killed, yet flower later in the season on new stems. In temperate sections there’s hardly a clematis that isn’t hardy. In the Deep South where exotic hybrids may not survive extreme heat and humidity, select species like the evergreen armandi and paniculata, or semievergreen texensis or montana rubens. Or try the tougher hybrids.

Culture of Clematis

Plant clematis where the top of the vine will get a minimum half day of sun, but the roots can be kept shaded and cool by a low wall, ground cover, or moisture-retaining mulch. A northern exposure may be dangerous in cold areas, but fine in warm. Don’t plant clematis near cedar, arborvitae, and other evergreens that harbor cedar rust. Allow space suitable to the vigor of the variety; six feet is usually the minimum.

Clematis like soil that is rich, porous, well-drained – and neutral or alkaline, never acid. If your soil is acid, mix in a generous quantity of horticultural lime (recommended quantities vary from a coffee can full to a spadeful per bushel of soil) at planting time; and add a handful or two every season afterward.

Failure in growing clematis can often be traced to careless planting.

Here is a step-by-step procedure:

• 1. From a reliable grower (best, a clematis specialist) get plants that are well rooted and two years old or more. These may be dormant, for fall planting, or pot-grown at any time.
• 2. Where winters are severe, plant in spring – but shade the vines against summer heat. In moderately cold areas fall planting is safe with some winter protection. In warm climates, plant at almost any time except before or during the flowering season.
• 3. Prepare a generous hole (two feet in diameter, three feet deep) and lighten and enrich the soil with leaf mold and aged manure. Add sand for drainage, and lime to sweeten acid soil. To perfect drainage, line the bottom of the hole with a two-inch layer of coarse cinders, pebbles or gravel.
• 4. Set the crown of the plant two inches below the soil surface (one inch if the soil is heavy), and pack soil lightly around the roots.
• 5. During or immediately after planting, provide a temporary support – string or bamboo stake – to protect the tender stem. This all-important support should come with the plant. Take care not to bend the brittle stem. Make sure it can’t be whipped by wind or broken by pets. Some growers circle the base with a collar of lead or hardware cloth; others set a bottomless flowerpot over the crown. Sometimes an arrangement of three or four stakes is sufficient.
• 6. Water thoroughly; then mulch with three inches of peat, peat and manure, or some other moisture-holding material. Don’t let the soil dry out during the first season.

Newly planted and established plants need cool, moist soil – but not soggy mud. As the roots spread out, spread the mulch farther – to a final minimum three-foot diameter. Since the roots are shallow, cultivate very lightly, if at all.

Any plant that flowers so furiously is likely to be a greedy feeder. The choice of commercial or organic fertilizer is yours. Feed in early spring, and again after flowering has finished, but not later than the end of September. Don’t omit the annual application of lime.

Supports for clematis need not be particularly heavy, and certainly should not overpower the plants. The leaf-stems will twist around anything suitably slim or narrow.

In cold climates winter care consists of mulching or hilling up soil around varieties that flower on old wood, so the tops won’t be killed back. Protect stems against rodents with a frame of chicken wire.

The mysterious wilt that can kill all or part of a clematis vine is not nearly so widespread as many gardeners think. But if the vine top should start to droop, cut it out cleanly and make a thorough application of fungicide to the vine and the surrounding soil.

Make a mental note of this: Clematis have been known to vanish completely for one or several years, and then reappear in perfect health. Don’t dig out roots of apparently dead plants for a good long time.

Clematis Pruning

For many clematis, little pruning is required except the occasional removal of dead or undesirable wood. Newly planted vines should not be pruned at all for two or three years, until their roots and top growth are thoroughly established. Herbaceous types die back of their own accord. For the rest, you need to know the flowering time, and whether the plant blooms on old or new wood.

For spring- or summer-flowering types that bloom on wood of the past year or year before, limit pruning to a, general cleanup of dead or damaged stems in very early spring, before new growth begins. The best flowers in this group appear at the top, so keep the height down.

Later-flowering clematis that flower on this year’s growth are pruned while still dormant, in late winter. Cutting back all stems to two or three feet or less is said to encourage new growth and larger flowers. On the other hand, a greater number of flowers may be produced when only dead wood is removed.

Clematis – Indoor And Greenhouse Culture

Clematis can be forced into winter flower about eight weeks after potting, if the soil is kept moist and the temperature not much higher than 60 degrees. Put dormant plants in four- or five-inch pots, with a rich, light, loamy soil mixture – plus generous lime (one tablespoon to a five-inch pot) if the soil is acid. Supply a three-foot stake or trellis immediately. Provide all possible sunlight.

After flowering, cut the stems back to about two feet, and store the plant in its pot, as cool as possible during summer, the soil just moist enough to keep the plant alive. After this three-month rest, prune away any dead shoots, repot in fresh soil, and return the plant to warmth and sunlight for another round of riotous flowers.

Growing Clematis in Outdoor Containers

The principles of indoor and greenhouse growing also apply here. And what a joy these vines can be in a summer container garden! The flowers are accessible, can be admired close-up, show off beautifully against the background of neat green leaves. The leaf-stems happily hook around almost any kind of thin support – wire, cord, trellis, or even slim-branched tree trunk.

Easiest to manage and usually in best proportion for tubs and other containers are the more moderate growers, and particularly those that flower on new wood.

In the fall, when flowering has finished, cut back top growth and store the plant in its tub or pot where it will keep fairly cool and barely moist until spring. When new growth begins, trim and prune neatly and start the cycle all over again.

Clematis Propagation

Ground layering in spring is usually safest and most satisfactory, particularly for the large-flowered hybrids. Pin the layered stem in soil in a pot, so the new plant can be severed and lifted without disturbing the roots. Midsummer stem cuttings of half-ripe wood (cut midway between the joints) will root in moist sand, shade, and humidity. Root division is also possible, but is tricky for other-than-experts. Seeds of species produce flowering plants in two years or more.

Representative Clematis Species List

Species clematis may not be so spectacular as the large-flowered hybrids, but they are usually easier to grow, less problematic, and hardy in more widely varying climates. As a guide to correct planting and pruning, they are grouped here according to time of bloom and whether they flower on new or old wood.

Species that flower in spring and early summer, on old wood, are pruned in early spring (March) – and then only to thin, shape, and preserve the desired framework.

Clematis alpina – Alpine clematis, one of the earliest, with three-inch blue-violet flowers.

Clematis armandi – Armand or evergreen clematis, only moderately hardy. Masses of two-inch white star-flowers in spring.

Clematis chrysocoma – Hairy clematis, new leaves covered with golden-brown fur; clusters of two-inch white or pinkish flowers.

Clematis Florida – Cream clematis, semievergreen in mild areas; four-inch flowers white with green and purple markings.

Clematis macropetala – Downy or big-petal clematis, with soft-fuzzy, nodding, blue-violet flowers.

Clematis montana – Anemone clematis, not reliably hardy in New York; but the variety rubens, with yellow-stamened pink flowers and bronzy-purple leaves has been grown successfully in Maine. Other varieties include alba, bountiful white star-flowers with golden stamens; and one usually listed as rosea ‘Apple Blossom,’ which may be a variety or hybrid of armandi. The soft, mauve-pink variety, undulata, is also probably a hybrid.

Clematis patens – Lilac clematis, southern native, with six-inch violet to white flowers.

Species that flower in late summer and fall, on new wood, are pruned in late winter (February), and cut back severely. They may be trimmed to five live buds, or to living wood, or to the ground if winter-killed.

Clematis apiifolia – October clematis, a beautiful ground or bank cover with white flowers.

Clematis drummondi – Drummond clematis, native of Texas and Arizona. Soft-hairy leaves and white flowers.

Clematis flammula – Plume clematis, hardy to Virginia. Airy clusters of fragrant white flowers.

Clematis languinosa – Woolly-leaved or Ningpo clematis, with fuzzy foliage and large white flowers. White flowers of the variety candida have orchid shading on the margins.

Clematis orientalis – Oriental clematis, with clusters of two-inch yellow flowers.

Clematis paniculata – Sweet-scented autumn clematis, semievergreen in the South, has been grown successfully in Maine. Lovely ground cover with clusters of small white flowers followed by silky seed pods.

Clematis recta – Ground clematis, more or less shrubby, with panicles of fragrant white flowers.

Clematis tangutica – Golden clematis, flowers early with small golden bells, followed by silvery seed pods. The variety obtusiuscula has yellow flowers like a dangling tulip, will accept shade, and is hardy in Massachusetts.

Clematis vitalba – Old man’s beard, traveler’s joy. Hardy, native ground cover with inch-wide, fragrant white flowers.

Clematis viticella – Italian clematis. Small clusters of rose-purple flowers with yellow stamens. Seeds may self-sow. Flowers of the variety kermesina, Kermes clematis, are wine red.

Some species may or may not be herbaceous, depending on climate and cultural conditions. When they die back, they grow up in spring from a woody rootstock and flower in summer or later. Where growth is not winter-killed, it should be pruned to living wood in March.

Clematis crispa – Marsh or curly clematis is a Southern native but has been grown with care in Maine. It bears slim, nodding, blue-purple flowers in midsummer.

Clematis jusca – Stanavoi clematis, with dangling violet pitcher-shaped flowers and brown-hairy leaves.

Clematis texensis – Scarlet clematis, may be listed as coccinea. It is easy to grow, and hardy to Maine. Flowers are like nodding scarlet urns, one inch long.

Clematis viorna – I.eather flower, native from Pennsylvania on down to Alabama. Dangling purple bell-flowers in July.

Clematis virginiana – Virgin’s bower, grows wild at the roadside as far as Canada. Good ground cover, with clusters of white flowers. Sows its own ripe seeds.

Clematis Hybrids

Most Clematis hybrids make a splendid display of brilliant flowers in early summer, with sporadic bursts of bloom after that until fall. Then, if they have been kept moist and fed well, they may repeat the original performance in nearly full glory. A few bloom only once, and later in the season.

Large-flowered hybrids that bloom in spring and early summer, on wood produced in previous seasons, are pruned in late winter, if at all. Cut back only half the stems to a point where new growth can be easily trained; cut back the other half the following year.

Family: Ranuneulaceae

Related Articles Of Interest:

• Clematis Hardy and Handsome Vine
• Clematis Vines, Plants, Flowers – Questions Answers
• Showy Clematis Vines and Outdoor Decorating
• Clematis Plants – Pests and Diseases