Starting a Bonsai

Photo credit by Changho Kim

This is a project that we did at our garden club a couple of months back. It was very easy to do and the results even at the very early stage were amazing. These are a lot of fun to do and would make for a good little income earner or fantastic gifts. One bonsai that was done at the meeting was then auctioned off to raise funds for the club. It attained the amazing price of $40. Just imagine something like a pine or fir tree done this way! At Christmas time bring it in and decorate it up and hey presto your very own miniature, living Christmas tree. I thoroughly enjoyed creating the bonsai and as soon as I can locate some cheap pots I am going to do a lot more. The two tree examples given later on in this piece make the most striking bonsais as both turn beautiful colours in the autumn. But you don’t have to use deciduous trees for this at all. Whatever tree you choose will give you years and years of joy and if cared for properly can be handed down from generation to generation for others to enjoy too.

There are several ways of creating a bonsai and the time each takes to work varies greatly. The method chosen really depends on personal considerations such as age or patience of the cultivator. The different methods follow similar patterns and are generally applicable to most types of tree.

From Seed

This is a very time consuming method and needs experience, much patience and discipline. The result can be a particularly fine miniature tree, as cultivation methods applied to young trees leave no trace. The method is also kinder to the plant.

Seeds collected from different trees are treated differently in order to make them germinate. Those contained in berries should be removed from the flesh of the fruit (rowan), others can be sown straight away (birch, elm) and others have to be kept cool in damp sand (maple, hornbeam, beech, oak). A very few types can simply be stored in a dry place (pine, spruce) after collection.

The individual tree descriptions explain in more detail which method is used for which type of tree.

In its first year from seed, the seedling is not cut back. In the spring of the second year it should be planted in a separate container, and the main taproot removed. The seedling reacts to this by developing especially strong side roots. In the third year the branches are also pruned for the first time. As long as the trunk is still thin, the shoots are allowed to grow 10-20cm (4-8in) long before cutting back. The longer the shoots are allowed to grow, the thicker the trunk and branches become.

Wherever a branch is pruned, a change in the direction of growth invariably follows. The structure of the branches is such that the gaps between the changes in direction get smaller and smaller from the trunk to the tip of the branch; thus each new shoot should be cut back shorter than the previous one.

The tree will develop faster and stronger if it is planted in the open from its third year and pruned regularly, although it can seldom be designed so precisely in the open as it can in a container.

Under no circumstances should a tree growing in the open be wired, as thickening occurs much too quickly. Growth is often so vigorous that the tree has to be pruned at three weekly intervals during the growing season – particularly important if you plan to go away on holiday. Elms, for instance, if not pruned regularly, can lose delicately developed branches because their tips become too thick from strong uninhibited growth. The following rule should perhaps be considered: if a bonsai is to reach an eventual height of not more than 30cm (12in), it will develop fast enough in a container. Plants, which you want to be taller, can easily spend several years in the open. How fast a young plant develops in a pot depends very much on general care as well. Watering the plant according to its needs is important, as is providing sufficient fertiliser, the correct position, and a good growing medium.

 Photo credit by Changho Kim

From Nursery Stock

When you visit a nursery or garden centre, you will often find one or two plants that are suitable for bonsai cultivation. Unfortunately, apart from varieties for hedging, the stock of native trees in nurseries is not especially large. Specialist bonsai nurseries occasionally stock young native specimens. These are five to ten year old plants, which have been cut back for several years and thereby prepared for cultivation as bonsai.

An advantage of using a nursery or garden centre plant for bonsai cultivation is that, although it has to be paid for, you are getting a tree, which has had a head start in terms of strong growth. One possible disadvantage is that it may have already developed relatively thick branches, which will have to be pruned, and occasionally when the trunk has to be cut back. The resulting wounds are large and take a long time to heal.

Apply the following principles to a nursery plant or young tree that is being chosen for bonsai cultivation: if the trunk has to be shortened a lot, the shape of the remaining length should fit the desired final form. The trunk should have branches from as far down as possible, and the root system should lie as much on a level as possible.

A nursery tree can be planted immediately into a temporary pot; it does not need to be kept in an open bed first as it should be strong enough already. Wooden boxes are ideal temporary containers. Plant the tree at such a depth that the roots remain clearly visible.

The method of shaping described below is only one of many. There are innumerable different possible shapes and the methods of cultivation are correspondingly varied.

After the tree has been planted in the box, select one side to become the front, using the root system, trunk and branches to help make the decision. Sometimes it is immediately obvious that some branches must be removed and this can be done straight away; or you can work systematically from the bottom to the top and will quickly recognise superfluous branches. Those remaining can be cut back to the right length and the larger cuts sealed with a wound sealant. The branches are then trained in the desired position with the help of wires attached to nails inside the box. The part-trained bonsai can remain at least a year in the shaping container. Then the wires should be taken off, the tree put in a first bonsai pot and the branches can be adjusted into the right position using wires.

From A Wild Sapling

Collecting a wild seedling is the oldest method of obtaining a plant for bonsai cultivation. But nowadays nature is so often spoilt by man’s carelessness that this can only be justified in rare and exceptional cases. There are places in the wild where you may come across old trees, usually deciduous trees such as beech, oak or hornbeam that have stayed small, possibly because they are growing near paths used by wildlife and so are regularly nibbled. Although they survive, they grow no taller, and with increasing age their trunks and branches thicken.

In mountainous regions, where the growing season lasts only a few weeks, you will often find small and very strangely shaped conifers: larches, spruce or fir. Stunted by hostile conditions in their natural habitat, these trees are nevertheless often quite ancient.

Plants that may to us seem dwarfed fulfil important ecological functions both near wild animal paths and in the mountainous regions. Some of these are particularly suitable for bonsai cultivation if by happy coincidence the root system, position of the branches and the size of the trunk have developed favourably.

Plants must never be taken from the wild without the permission of the relevant forest or national park authority.

Sometimes digging up trees can save them from inevitable destruction, where for example they might be growing on a building site waiting to be mown down by a bulldozer, or simply have been uprooted in a storm. If you want to collect a tree from the wild bear in mind the following points necessary for their survival: dig far enough around the base of the tree to reduce root damage and keep the roots covered and moist. If at all possible enclose the whole tree in a plastic bag large enough to allow the bag to be sealed completely over the tree.

Acer palmatum 

Japanese Maple

Outdoor

Japanese maples are amongst the most beautiful trees on earth. Their slender, arching branches support an open canopy of delicate lobed leaves, whose subtle colours intensify to brilliant reds and oranges in autumn. They are naturally very graceful and elegant trees, and this aspect is echoed in bonsai. Heavy trunks and rigid, geometric branch formations look entirely out of place with this species.

These maples are notoriously variable when grown from seed, which means that there are countless different strains available for bonsai. It is not uncommon to find that each tree in a consignment differs in some way from the others. The leaves – which usually have five or seven lobes, can vary in spring from bronze, through orange to bright red; turning to various shades of green in summer, often with red margins.

The shoots – often coloured red or orange – are fine, and grow prolifically from internodes on old wood or from around pruning wounds. These clusters of shoots must be thinned out, leaving a maximum of two at any one point. Failure to do this will result in swollen knotty structures, which will look unnatural and will spoil the elegance of your bonsai.

Large-scale production of commercial Japanese maple bonsai unfortunately leads to a number of poor quality examples in each shipment. Faults such as uneven roots or ugly pruning scars are, sadly, not uncommon, so consider each tree carefully before deciding which one to buy.

Where To Keep Japanese Maples

Japanese maples should be kept outdoors at all times except during periods of heavy frost, when they should be brought into a frost free outhouse. They can be displayed indoors for a few days at a time while they are in leaf or for an hour or so in winter.

Japanese maples will tolerate full sun so long as the roots are not allowed to become too dry, and they are not exposed to strong winds, otherwise the leaves will scorch. In practice, semi-shade and wind protection are advisable.

Maintenance

Re-potting: Every one to three years in spring, as the buds begin to elongate and adopt a sheen. Use Akadama or the standard soil mix. Add some sphagnum moss in hard water areas.

Pruning:  Best done during the spring, two weeks before re-potting. Pruning branches in midsummer results in masses of new shoots from the internodes.

Pinching:  Pinch out the tips of all new shoots when two or four complete leaves have formed. Repeat as necessary throughout the year.

Watering:  Japanese maples require slightly acid soil conditions, so use rainwater instead of tap water if possible. Keep soil moist at all times, avoiding both water logging and dryness. Spray foliage regularly.

Feeding:  Balanced feed from bud burst until late summer followed by lo or zero nitrogen feed. Apply soil acidifier twice a year in hard water areas.

Beware! Aphids colonise young shoots in spring and distort the new leaves. In winter, a cold wind can kill fine shoots, in summer leaves can become scorched by little more than a gentle breeze, so protection from wind at all times is essential.

Zelkova serrata

Zelkova/Grey Bark Elm

Outdoor

Although closely related to elms, Zelkovas are in fact a distinct species. Their natural habitat is that of the archetypal tree: a straight, cylindrical trunk which is clear of branches for about two metres (approximately 6 foot), at which point it divides into a number of branches which fan out and fork uniformly in all directions. At the periphery the twigs become very fine and bear neat pointed oval leaves.

Zelkova bonsai follow the same pattern in miniature and are created by shortening the trunk of a young sapling in mid-summer and training the shoots that emerge from the wound into branches. Very little wiring is necessary because the growth is uniform and generally well-distributed, allowing the fan like branch structure to be developed by pruning alone.

The bark remains smooth and relatively featureless throughout the tree’s life, but this is in total harmony with the elegant and gentle tapering of the branches into the tracery of fine twigs. A gnarled or fissured bark would look incongruous on such a tree.

In the wild, Zelkovas naturally form a large dome shaped tree. This habit is echoed in bonsai, and a convincing little tree like this can be achieved in just a few years.

Some nurseries offer a plant called ‘Zelkova sinica’ but these are generally a variety of Chinese elm (Ulmus parviflora) which has been renamed – probably to avoid import restrictions.

Where To Keep Zelkova

Zelkovas are perfectly happy in full sun although in really hot weather the leaves may scorch or become yellowish and leathery and little use to the plant. Regular spraying can help prevent this but it is more practical to put the tree in semi-shade for the summer, returning it to the sun in late summer or early autumn to enhance the autumn colouration. If kept in semi-shade all year the leaves will retain their spring colour – a bronze tint often edged with deep red – well into summer.

In winter the roots will withstand considerable periods of freezing but the delicate fine twigs may die back, especially if exposed to wind for just a short time. Winter protection from the wind is mandatory.

Maintenance

Re-potting:  Every 1-3 years, depending on the size and age of the tree, in early spring. Pay attention to the formation of the root buttress at the base of the trunk and prune away crossing or unsightly roots. Use standard bonsai soil or Akadama.

Pruning:  Prune unwanted branches in early spring, two weeks before re-potting. Strengthen weak branches by pruning them hard in mid-summer and allowing the resulting new shoots free reign until autumn.

Pinching:  Pinch out the top of all new shoots as soon as two leaves have formed. This may well become a weekly task in summer.

Watering:  Keep the soil evenly moist throughout the year. Spray the foliage at each watering to keep it fresh and spray the trunk to keep it free of algae.

Feeding:  Balanced feed from spring to late summer then change to nitrogen free until the leaves have turned colour.

Beware!  Zelkovas can become congested, especially at the top, which can result in die-back of many fine twigs. Regular thinning of crowded areas is essential.

Any tree can be cultivated into a bonsai including fruit and citrus trees. When re-potting the bonsais just place them into a slightly larger pot. Bonsai pots are shallow and look very similar to a ceramic baking dish with a hole in the base at the centre. To make the base of the tree more attractive you can use sphagnum moss. This can be mixed with a small amount of cow manure too. This will help retain moisture to the roots and also provide a small amount of fertiliser at the same time if the moss is mixed with the manure. Make sure that you use dried cow manure or you could burn the young tree. Place a nice uneven shaped stone or small rock on the moss to add to the attractiveness of the overall look.

Happy Bonsai growing