Wall plants are a wonderful asset in a garden: they look beautiful and for the most part, they do their own work.
A wall plant or climber is one whose stem at maturity cannot support its plant growth vertically, so it must either scramble along the ground or lift itself by climbing. Some climbing plants, such as honeysuckle, twine clockwise, while others, such as clementis and nasturnium, have leaf stalks that can twine onto twigs, wire or any small support.
With sweet peas, the leaflets transform onto tendrils that grip onto any twiggy supports. Some plants, such as climbing roses, have backpointing thorns that enable them to edge their way up through bushes. Still others, such as the Virginia creeper, have small adhesive pads that clamp onto trees or rocks and walls, which they can then cover with a close mat of leaves.
Ivy, which produces small rootlets that embed themselves in tree bark or interstices of walls, cling tightly to their host without drawing nourishment from it.
You can use climbing plants on walls, arbors, trees, screenings and fences and as both cover or boundary-fence cladding.
In planting, remember that climbers, as most shrubs, are best planted October to December (or failing this, March to the end of April). Much may depend on the plants' availability.
For training: A few plants, such as ivy and Virginia creeper, are self-clinging, but some need support.
For plain brick walls, the fixings can be permanent and are best provided by driving screw-eyes into the wall in vertical lines a foot or 18 inches apart and protruding two to three inches from the wall. Over arbors and trees, nails and such are usually not necessary; plants chosen for these types of climbing usually climb upon their own previous growth.
In pruning climbers, use sharp secateurs that cut without tearing or bruising and always cut just above the node. When cutting out older wood, one inch and above, it is necessary to use a pruning saw. Avoid leaving snags or short stubs, which look ugly, will often die back and may even cause disease.
Some pruning may be necessary while a plant is being trained. When any stem or branch is cut, the topmost bud left will almost invariably be the bud that "breaks" and produces next year's shoot. Consequently, a stem or branch that is growing away from the part of the wall that it should cover can be pruned back to a suitably positioned bud that will break and produce a shoot to cover the intended area.
Here are some ideas for good climbing shrubs and plants:
Camellias are usually grown in light shaded areas as free-standing shrubs against north or west walls or trained on the walls themselves. A suitable system of support wires is necessary to tie them to the wall, and then it's merely a mater of tying in shoots as they arise.
They prefer peaty soil and can be propagated by leaf-bud cuttings. There are thousands of cultivars available, but a few well known and reliable ones:
* 'Alba Plena,' a double white;
* 'Donation,' orchid-pink, large semi-double;
* 'Francis Hander,' a single white;
* 'Captain Rawes,' a hardy, double carmine-pink.
Wintersweet has fragrant flowers in the depth of winter and is grown well as a wall plant. Wall protection actually induces slightly earlier flowering. The flowers are small, about one inch in length, and have an outer ring of pale yellow petals and an inner ring of dull purple. On mature plants, a few flowers will sometimes give out a light green, flask-shaped fruit.
Clematis has flowers that bloom from January to October; they can vie with the rose for the place of the supreme flowering climber. They climb by twisting their leaf stalks around a suitable twig or stem and are at their best climbing up and through some supporting bush or tree. As wall plants, some form of wire or lattice for support is essential.
Some good candidates for climbing clematis are:
* 'Barbara Dibley,' a violet with dark-carmine stripes along each petal;
* 'Blue Gem,' which is sky-blue;
* 'Duchess of Deniburgh,' a large double white, slightly scented flower;
* 'Lady Londesborough," a pale mauve with dark stamens.
Cathedral Bells is a perennial climber that climbs by means of tendrils at the ends of its leaves. The flower is carried on an open stalk. It opens as a pale greenish-purple trumpet and becomes darker purple as it develops and sits back on a green sepal that folds back to give the "saucer" effect. There is a white 'Flore Albo' and one with variegated leaves.
Fuchsias are good wall plants, particularly where the border in front of the wall is narrow. Even the taller kinds, if planted fairly close to the wall, will take up little more than two or three feet.
The hardiest of the taller fuchsias is 'Riccartonii,' a typical fuchsia-shaped flower with scarlet and a skirt of violet petals and long stamens. 'Versicolore' is also widely grown and has gray-green leaves and irregularly variegated creamy-white backing for its scarlet flowers. 'Mrs. Popple' is scarlet and violet.