The planting distance of pleached trees will depend on various factors, including species and the final desired effect. The trees can be planted so that each screen is just touching for immediate effect, although it would be advisable to leave at least a few feet to allow for growth. This distance of planting will give a deep bushy screen. Depending on patience (and budget) the trees can be planted with up to 10-12 feet between the widest parts of the screens. Over time these branches will grow out to meet one-another creating a slightly more narrow screening effect.
To prune and maintain pleached trees it helps to think of it as a two stage process. Firstly, the pruning required to train and tie in the newly forming tree, called ‘formative’ pruning. Secondly the pruning required to maintain the shape and form of the more mature pleached tree, known as pruning for ‘shape’.
In formative pruning, (which is only relevant to establishing a new pleached tree if starting from scratch) as young laterals are bent downward and tied in to the bamboo framework any excess laterals and stronger sub-laterals that are not growing in the plane of the tree should be pruned back to within a few centimetres of the stem. At the same time branches that are growing above the required overall height should be cut back to below the top of the frame.
Any branches that are crossing each other should be removed at an early stage. Crossed branches can rub on each other, and as they subsequently don’t heal, cause wounds that can lead to disease entering the tree. Tie in with soft twine or plastic tubular ties to avoid cutting into the tree. Older ties should be checked regularly and replaced if they are too tight, as they can cut into the tree as the branches thicken.
Tying in and formative pruning should be done several times during the growing season, with a final prune in October. When pruning to maintain the shape of a pleached tree it is important to first remove any diseased or damaged wood and also any broken branches. It is then a relatively simple matter of pruning the tree to maintain the shape. This should be done once or twice a year, late winter being a good time to assess winter damage and trim the tree before the spring growth obscures the framework of branches.
Once you have an established and mature tree it should be possible to cut away the old bamboo framework, to show your pleached trees at their best. Many of our mature pleached trees are at this stage in their development.
Espaliers require a more formal approach to pruning, the tiers are trained at regular spacings and each winter all upward growing laterals are cut back to around 5cm, to a bud, to form ‘spurs’ that will bear blossom and fruit the following year. Each tier can be extended until the desired final width of the tree is reached.