Horticulture Principles and Practices

Eucalyptus and Paulownia are amenable to such treatment. Coppicing and pollarding
both have dwarfing effects on plants.
19.13.3 PLEACHING
Pleaching is a technique used to weave together the branches of a row of trees that, with
appropriate pruning, can develop into a hedge. Species adapted to this kind of treatment
include linden, hornbeam, and holly.
19.13.4 TOPIARY
Topiary may be described as the art of plant sculpture in which plants are trained and
pruned into formal shapes. These shapes may be abstract or geometric and sometimes
may be readily recognizable objects such as animals. Topiary may be created in container
plants, in the garden, or in the general landscape. Sometimes the top of a hedge is capped
with a topiary.
The simplest designs are those closest to the natural shape of the plant. To create
complex forms, a metal framework is first designed and placed over the plant so that it
grows into and over it. The plant is then carefully clipped to shape, following the outline
of the framework. Horticultural techniques such as pinching, training, and tying are used
to encourage dense growth to cover and hide the framework. When pruning, a straightedge
and other guides often are required for accuracy. Without such guides one may cut
too much on one side, which may require that the whole piece be reworked to obtain the
geometric symmetry desired.
Geometric shapes are difficult to create and maintain. To keep them attractive, the
sides and surfaces must be properly cut to the symmetrical, sharp, and well-angled
shapes. Round shapes are relatively easier to create and maintain. It is very important to
use sharp tools in pruning and for the operator to exercise patience, proceeding cautiously.
Common and more or less standard shapes are the poodle or cake stand and the
spiral (Figure 19–19). To create complex and irregular shapes, one must be very creative
and patient. The species most frequently used for topiary include those that are easy to
train such as yew (Taxus), boxwood (Boxus), and bay (Laurus nobilis). These plants are
evergreen and long-lived.
Topiaries need to be maintained to keep them in form and attractive. Like all plants,
they require fertilizing and watering to enable regrowth after cutting. They also need frequent
routines of maintenance clipping during the growing season. The frequency of
clipping depends on the species, plant vigor, form, design, and demands of the owner. If
owned by a perfectionist who must have the plant in great shape all of the time, very frequent
pruning will be required. Species such as the yew can be presentable with about
two clippings per year. However, if the design is geometric, a monthly schedule may be
required to remove any new growth. Over time, certain portions of the plant may become
damaged and require repair. The damaged part should be removed and a nearby shoot
trained to fill the gap. Depending on the damage, it may take up to several years to restore
the topiary to its original form.
Topiary
Training and pruning of
plants into formal shapes,
sometimes geometric or
abstract but highly stylized.
19.14 TRAINING AND PRUNING FRUIT TREES
Fruit-bearing tree training goals are similar to those of ornamental trees. These goals
include the following:
1. To develop strong branches to bear the weight of fruits.
2. To properly space and retain an appropriate number of branches for enhanced
productivity.
3. To control the time of first fruiting. While fruiting should not be delayed, the
quality of fruits and the duration of fruiting period are increased when trees
19.14 Training and Pruning Fruit Trees 585