Wall plantings can soon become overgrown, often resulting in poor flower and fruit production. In some cases it is best to remove the plant, but many can be hard pruned
Which plants to renovate
Wall plantings that have outgrown their allotted space, or have started to decline but are basically sound, can often be renovated. This is usually carried out in the dormant season for deciduous plants such as Chaenomeles and honeysuckle, or early spring for evergreens such as Pyracantha (left) and Passiflora caerulea. Sickly plants, which cannot be brought back to full health, are best removed and replaced.
Simple measures
Plants such as the wall shrub Ribes sanguineum tolerate drastic pruning and can be cut down to approximately 30cm (12in) from the ground. However, removing all existing wood often means that flowering will take several years to resume.
More gradual approach
Many deciduous and evergreen plants do not tolerate this kind of drastic treatment and it is better to carry out pruning over two to three years. Each year, cut back one in three of the main stems to ground level, reducing the rest to half their length.
Use appropriate equipment to carry out such a job. Loppers can be used for thick and woody stems up to 3cm (1.25in) wide, while a pruning saw is ideal for thicker trunks. If growth is congested or twining, it is a good idea to remove it in small sections.
At the same time, clear dead, diseased and damaged wood from the plant and any weak, spindly stems. Use the opportunity to remove debris from behind the support. Detaching a climber from its support and laying it flat on the ground often makes it easier to sort out the tangle of shoots. This also enables maintenance work to be carried out on walls, fences and wooden supports.
Promoting healthy growth
To encourage strong growth in spring, apply a slow-release fertiliser at 120g per sq m (4oz per sq yd) and mulch round the plants to conserve moisture. Water well in dry spells. During the course of the season, tie-in strong new growth to fill gaps in the framework (left). In year two, thin out new growth and cut back half the remaining older branches. In the third year, remove any remaining older stems.
Some climbers, such as wisteria, produce thick woody stems that may have to be removed before younger growth from the base can be tied in. These should be cut away in manageable sections, and if the work is substantial or involves working from ladders it may be wise to employ a professional tree surgeon.
Training newly planted climbers and wall shrubs
Pruning established climbers and wall shrubs