Clematis are amongst the most prized of all climbing plants, and the large flowered hybrids can be most spectacular when well placed m the garden. But they can be annoyingly temperamental in establishing themselves, so time spent in preparing the soil, which should be a good garden loam with the addition of well-rotted manure, peat or garden compost, and choice of planting position should be amply repaid by success.
Often the soil conditions chosen for planting Clematis is far from ideal, soils in beds at the base of walls can often be ‘hungry’ and very dry. Similarly soil around tree trunks and established shrubs can be impoverished and since Clematis are gross feeders mulching annually with well rotted manure, peat or compost, plus an adequate supply of water in dry conditions is essential.
Since all our Clematis are grown in pots, they may be planted at any time of the year, although it is wise to avoid the cold period between December and February. Clematis should be planted with their roots in the shade and the flowers in the sun. Therefore when planting Clematis to ramble through shrubs and trees, plant on the shady side, and when planting to climb a wall, plant a small shrub in front to shade the roots or place a large stone or slate in front of the plant.
Generally speaking. Clematis are best planted in full sun, the sun ripens the wood and they flower profusely. But there are varieties which will do equally well on north facing aspects The flowers of varieties such as Nelly Moser, Mrs Hope, Barbara Jackman tend to fade when exposed to the sun, but in a shady position their natural colouration remains.
Clematis range in colour from white through pink and red to every shade of blue and purple; their uses are legion, and we suggest a few of these below: (a) climbing up the walls of houses and sheds, b) on porches, pergolas, arches and low walls,
(c) among pillars or ‘tripods’ in the shrub border,
(d) over spring flowering shrubs and low forking trees
(e) covering unsightly objects in the garden (the moniana varieties are best for this),
(f) for cut flowers, especially when placed in bowls.
Pruning
This is very important. All large flowered hybrids in their first year should be cut down in the spring to a healthy bud to within 9-1 2 ins of the ground.
The species should be tied out to form a framework, and these branches should be cut down to 2 ft after the first year’s growth.
In subsequent years, the species should be pruned as necessary to keep them under control. The large flowered hybrids should be pruned according to the time of year at which they flower. Those flowering after 1st July, these include varieties belonging to the jackmanii, texensis and viticella groups, may be cut down to within 12-18 ins of the ground each year. Varieties belonging to the florida, lanuginosa and patens group and flowering in May and June on the previous year’s wood only need to be trimmed back and old flowering growths removed after flowering.
The letters after the name of the variety indicates to which group it belongs.
Large Flowered Hybrids
‘Barbara Jackman’ (J). Soft pink with a plum-coloured bar; best on a north or north-west wall. May-June.
‘Beauty of Worcester’ (L). Deep blue with white stamens, producing double and single blooms on old and young wood respectively. June-September.
‘Bee’s Jubilee’ (L). Mauve-pink sepals with a central bar of carmine, brown stamens. June-September.
‘Comtesse de Bouchard’ (J). Delicate satin rose flowers, a little smaller than some varieties. June-September.
‘Duchess of Edinburgh’ (F). Rosette-shaped, double-white, scented. May-June.
‘Ernest Markham’ (V). Glowing petunia-red, with velvety sheen. Free flowering. July-September.
Gypsy Queen’ (J). A sumptuous velvety-purple. The deepest shade in this colour. July-August.
‘Hagley Hybrid’ (J). Shell-pink, with brown anthers and pointed sepals. Very free flowering, June-September.
‘Henryi’ (L). Pure white with dark stamens. Enormous flowers up to 6 ins across. June-July.
‘Jackmanii Superba’ (J). An improved form of the most popular variety. Dusky violet-purple, very free flowering. July-September.
‘Lasurstem’ (P). Deep blue flowers with yellow stamens. Free flowering. May-July.
‘Marie Boisselot’ CMme le Coultre’) (P). One of the most attractive white flowering clematis. Sepals are large and overlapping with a central boss of cream stamens. Very vigorous and free flowering. June-September.
‘Mrs Hope’. Satiny mauve with a darker bar. July-August.
‘Nelly Moser’ (L). Light mauve with a red bar. The favourite striped variety. May-June.
‘Prince Hendrick’ (P). Deep azure-blue, with pretty frilled sepals. Very large flowers. July-October.
‘Rouge Cardinal’ (J). Velvety-red – a superb new introduction for both colour and texture. June-August.
‘The President’ (P). Purple suffused claret. June-July and September.
‘Ville de Lyon’ (V). Carmine-red, smaller flowers than most varieties. July-October.
‘Vyvyan Pennell’ (P). This variety always attracts attention, the large violet-blue flowers suffused purple and carmine are fully double and produced from May through till July. Occasionally single flowers will be produced later in the year.
‘Wyevale Blue’ (J). A lovely shade of soft lavender-blue, exceptionally free flowering. An excellent variety. July-September.
Species
alpina ‘Frances Rivis’. A charming, slender climber particularly suitable for growing over a low wall or into small shrubs and conifers. The large, nodding, violet-blue flowers are carried on long slender stems.
armandii (E). Prized for the clusters of very fragrant white flowers in May. The large, leathery foliage persists all year. Best on a south or west wall. 15ft.
macropetala (The Downy Clematis). A captivating climber, with nodding semi-double blue flowers. It will reach 15 ft and should be given a favourable position. Remove weak shoots in February. Flowers in May and June, and sometimes again in the autumn. Needs a sheltered spot. 15 ft.
‘Markham’s Pink’. Similar to the above, but with lilac-pink flowers. 15 ft.
montana. A vigorous climbing shrub, with masses of almond-scented white flowers in May. An excellent variety for rambling over trees, walls, sheds, etc.. but not quite as good as C. spooneri. 20 ft plus.
rubens. Similar to th’e above, but the flowers are rosy-pink. The young leaves are bronze. 20 ft plus.
‘Elizabeth’. As the above variety; the flowers are slightly larger and more scented. 20 ft plus.
‘Tetrarose’. Similar, but the flowers are a little later, possibly slightly larger. Young foliage bronze. 20 ft plus.
orientalis ‘Orange Peel’. Bell-shaped llowers, consisting of four yellow waxy sepals, thick as orange peel. A vigorous twiner, becoming a mass of tangled growths with delicate fern-like foliage. 20 ft plus.
spooneri. Similar to C. montana, but the white flowers are larger and of more substance. The juvenile bronze foliage contrasts admirably. 20 ft plus.
tangutica. Rich yellow, lantern-shaped flowers in August and September are followed by the feathery grey seed heads which give a lovely effect throughout the winter. Habit and foliage similar to C. orientals, but less vigorous. 10 ft.
Clematis are woodland plants and to obtain the best results, we recommend that you try to simulate these conditions by planting in a cool, moist, but well drained situation to provide a suitable ‘root run’. At the same time, bear in mind that these plants like to grow into the sunlight so try to think of them as plants which require to have their ‘feet in the shade’ and ‘head in the sun’. Although the varieties Nelly Moser, Bee’s Jubilee and Barbara Jackman, varieties which tend to bleach in the sun, will hold their colour better if planted on a sheltered north or west wall.
Contrary to a wide belief the modern Clematis is a perfectly hardy plant, and a firm support is required for the best results. Provide a wire mesh of suitable dimensions if required for walls or fences, otherwise they can be allowea to ramble through existing climbing plants, etc., providing the supporting plant requires pruning at the same time as the Clematis, i.e., a Climbing Rose, but not Rambler Roses, most of which are pruned during the summer.
A rich soil of an open loamy mixture, enriched with well rotted manure with bone meal added, makes an ideal growing medium, and a clay soil can easily be treated to obtain these conditions, as well as a light sandy soil.
Plant firmly after removing the plant from its pot, and ensure that the crown is at least 2 ins below the surface, mulch annually with old manure or a good compost, with bone meal and dried blood forked in. At all times take care to avoid kinking the stem.
Clematis Wilt
Clematis, especially jackmanii types and some other large flowered garden cultivars, are often affected by a wilting or dieback of shoots. This trouble is usually known as Clematis Wilt and in the past it has been attributed to many different causes, such as bad drainage, malnutrition, graft failure, insect or chemical damage. In recent years, however, it has been found that the fungus Ascochyta Clematidina can cause Wilt, and it is now regarded as the major cause of dieback in outdoor plants.
The fungus enters the plant fairly low down, and unfortunately, the first symptoms seen are usually the sudden wilting of the upper parts of the shoot, the youngest leaves drooping first, and the leaf stalks blackening where they join the blade. Wilted leaves die rapidly within an interval of a week or so between the onset of symptoms and complete collapse. Wilted shoots never recover but young healthy shoots sometimes develop below soil level or from nodes immediately beneath the wilted region. In any case the Clematis plant is rarely killed outright in one season.
On closer examination of the affected parts a discolouration of the stem can be seen or even small rotting patches, under the lowest pair of wilting leaves. Often, however, these symptoms are not noticed because they occur so low down and may be below soil level.
The fungus produces very small fruiting bodies on the cut stumps of old stems and from these minute spores stream out and spread the disease from one part of the plant to another, or even from one plant to another.
There is no need to dig up an affected plant but the wilted shoots should be cut back to clean living tissues even if this means going down to below soil level. The wounds, however small, should then be painted with a good protective paint such as Medo or Arbrex. New shoots when produced, either later in the season or the following spring should be sprayed with a copper containing fungicide such as Bordeaux Mixture or Liquid Copper. It is a good idea to spray all Clematis plants in the spring when the shoots start to develop with such a fungicide, as this should help to prevent attacks of the disease. Two or three applications can be given at fortnightly intervals.
