Whilst individual bonsai specimens can take a number of years of training to create a strong visual image, well designed group plantings can be far more instantly satisfying.

Group plantings replicate a number of trees growing together in a copse, wood or a forest and reflect the interplay between the trees and their branches as they compete for light and nutrients.

Successful groups can be created using young, thin trunked plants with little taper, that would otherwise have little use as individual bonsai specimens without considerable training. Successful group plantings are not so reliant on the material used; it is the artists creativity that makes for satisfying results.

OBTAINING TREES FOR GROUP PLANTINGS

Most species can be used for group plantings, though species that have naturally upright, branching habits are preferable. Small leaved species are most suited to small and medium groups whilst coarse growing or large-leaved species suit taller plantings.
Particularly recommended are; beech (Fagus), birch (Betula), Cryptomeria, elms (Ulmus or Zelkova), hornbeam (Carpinus), juniper (Juniperus), larch (Larix), spindle trees (Euonymous) and maples (Acers).

Group plantings are usually composed of one species only as this creates a more natural look and is far easier to style successfully. It is possible to include more than one species in a group but this not only disrupts the image and scale but can also cause problems due to the differing cultivation requirements of each species that is used.

When purchasing trees for group plantings, it is necessary to obtain trees that have more slender, upright shapes preferably with a number of short branches emanating from the top 2/3 of the trunk. It is not necessary to have tapered trunks though trunks with a distinct inverse taper are still unsuitable. Trees should have a range of heights and trunk thickness to enable the creation of depth to a group planting. Any number of trees from 3 upwards can be used though it is highly preferable to use an odd number unless the group consists of 15+ trees. It should be noted that with plantings of 5 trees or less it is harder to convey a feeling of depth to the work. An even number of trees in a group planting is supposed to be unlucky, it is also more difficult to arrange successfully. Always have a greater number of trees available to you than will be required so you are not restricted in your design as you actually construct the planting.

Preferably trees that are being prepared for a group planting should have small, compact rootballs to enable easy positioning in the container.

Japanese Larch Group Planting by Harry Harrington

POTS FOR GROUP PLANTINGS

An impression of space is very important when creating group plantings and a large shallow container contributes to this sense of space. Deep containers need to be avoided unless the trees used in the group planting have thick trunks. A shallow container should be no deeper more than twice the width of the thickest trunk to be effective. It is very important that after positioning your trees in the group planting they are unable to move, as this can damage fine roots as they start to spread out into the compost and will also destroy the image you have created. To anchor your trees into position until their roots have inter-twined and are able to hold still themselves, anchor wires must be used. When preparing the pot, bars of bamboo or sticks are tied into a frame at the base of the pot; anchoring wires can be attached to this frame where necessary. When repotting the group-planting in 2 or 3 years time, the roots of all the trees should have fused together and the anchoring wires and frame can be cut out.

Instead of a pot , slabs of rock or slate are sometimes used and with care a very natural look of trees growing in the mountains can be achieved. Slabs of stone can be prepared for rock plantings by drilling drainage holes in the rock to allow excess water to run off. Anchor wires are glued firmly in position on the surface of the rock and are used to hold trees in position. A 'wall' of clay mixed with peat is placed around the edge of the slab to keep the compost from running off.

DESIGNING A GROUP PLANTING

A bonsai group planting creates an illusion of perspective by using a number of visual tricks often used in drawings and paintings. Perspective is created by drawing the eye to a number of focal points that subconsciously fools the viewer.

Tall trees are positioned at the front of the pot and smaller trees toward the back create a feeling of greater depth than the actual width of the container.

Trees in nature vary in height and trunk thickness and this should be reflected in your design, the tallest trees should have the thickest trunks, the smallest trees the thinnest. Symmetry in group planting will always draw the eye and should be avoided, trees should be planted at unequal distances from each other and according to height.

A sense of perspective can also be created by creating sub-groups of trees so that the entire group will consist of 2,3 or more smaller groups. For the viewer this also leads the eye through the trunks of the planting to the smallest trees at the back, re-enforcing the sense of perspective.

The silhouette of the planting as a whole should be triangular with the two sides from the apex tapering away at different angles. If the silhouette of the back ground trees is kept simple, attention is drawn to the trunks and branches of the trees at the front, the rear trees become less distinct and therefore further away in the eye of the viewer.

POINTS TO OBSERVE WHEN DESIGNING A GROUP PLANTING

There are a number of useful guide-lines that can be followed when designing your group planting that if followed will greatly enhance the final outcome:
 

Do not arrange the materials at random. No trees should be parallel to each other.

Use shallow, wide containers and leave enough empty space to simulate the vastness of land.

The tree with the thickest trunk is the focal or primary tree and should be planted towards the front along with the secondary tree.

Shorter, thinner trees should be placed towards the back in order of importance, with the smallest tree at the very rear of the container.

No three trees should be in line with each other from ANY angle.

The primary tree should incline slightly forward at its apex to create a sense of height.

The primary tree should be planted highest on top of the soil in the container, the smallest tree should be lowest.

Trees to the right and left should be arranged so that when viewed from the front or sides of the composition, no tree conceals another.

Trees at the front of the group should have branches that start higher up the trunk to allow the viewer to be able to glimpse through
the planting. Trees at the back should have branches that start to grow from a lower position.

Branches should grow out from trunks uniformly, this creates cohesion to the composition and reflects the fact that all the trees would be subject to similar growing conditions as each other in nature.

Consider the effect on the growth of the trees by areas lack of light and shading. The dominant tree will never of lacked light at its apex as it grew and will have grown straight. Lesser trees in the composition would have to search for light in the shadow of the primary tree and this would result in trunks that lean away from the primary tree.

Consider the effect on the growth of branches that are in the shadow of other trees. Branches that face into the centre of the composition should be very short or missing from lack of light, however branches growing on the outside of the group would search for light and will be far more numerous and vigorous. These branches also help form the silhouette of the composition as a whole.

The overall silhouette of the planting should be that of an asymmetrical triangle.

ARRANGING THE TREES IN PRACTICE

Group plantings should only be assembled in Spring at the time when individual specimens of the species would ordinarily be root-pruned and repotted.

Fill the container with a shallow layer of soil and start to arrange the trees in the pot starting with the primary tree and working backwards towards the weakest tree.

The following series of pictures illustrates the assembly of a group planting of Cryptomeria japonica 'Yatsubusa' by Harry Tomlinson in his book "The Complete Book of Bonsai". It demonstrates how using the above guide-lines, a simple but very effective group of five trees can be assembled.

<(1) Position the tallest tree first about a third of the way in from one side and towards the front of the pot so the tree stands closest to the viewer.

>(4) Place the thinner trunked fourth tree at the back of the container to increase perspective and the fifth tree leaning out slightly on the extreme right of the composition to complete this five tree group.


 

After positioning the group, the trees should be firmly tied into the pot and soil can be worked in around the tree roots and watered in.

This is by no means the only layout for a group planting; there are an infinite number of variations that can be used. Below are a few suggestions for layouts of differing numbers of trees.

GROOMING AND FINISHING BRANCHES

When the planting has been thoroughly watered in, branches can be groomed. Remove downward growing shoots and any branches that cross to open out the structure. Prune back branches so those at the top of each tree are shortest and each branch as you travel down the trunk becomes gradually longer; ensure that the branches of each tree create a triangular silhouette to the overall composition. Generally, you need prune to create numerous short branches.

Some branches may be growing at awkward angles at present but do not attempt to wire them into position for at least two months so the group has enough time to settle in and the trees can recover from transplanting.

Maintenance pruning in the future consists of keeping branches shortened and occasionally thinning out congested areas of foliage.

UNDERPLANTING AND MOSS

Under planting with small plants or moss can be used to complete the image of a group of trees in nature. Moss is often used to represent grass in group plantings.

Ensure that anything used as a underplanting is in scale with the trees themselves. Position moss in the planting where grass would be able to grow around a group of trees; reflect the lack of light around the base of the trees by leaving bare soil.


REPOTTING
Group plantings need repotting and root pruning at the same intervals as individual bonsai specimens and at the same time of year. However, it is worth leaving the first repotting of a new group for a couple of years. Before then the root-systems of each tree will not have grown enough to become inter-connected and there is a danger that upon removal from the container, the composition may fall apart and have to be reassembled.

Upon removal of an established planting from its container, remove old soil from the outer edges of the rootball, cutting wedges of roots as you go. Always inspect the roots to ensure that each tree in the composition has sufficient roots of its own to support its foliage.

The soil in the centre of group plantings becomes very compact and dense, eventually becoming impenetrable for air and water. Every time the group is repotted, soil should be replaced from localised areas in the centre of the planting by gently displacing it with the aid of a thin stick and/or a narrow jet of water, and replacing it with fresh soil.


CARE OF GROUP PLANTINGS
Care for group plantings is very similar to that of individual bonsai specimens of the same species though extra care must be made to ensure that all trees within a planting receive sufficient water and fertiliser. Group plantings should be turned once a week to ensure that all trees in the group receive enough sunlight.