Frequently Asked Questions - FAQ

Is a Bonsai a particular Species of tree or plant?
Are Bonsai trees ment to stay Indoors or Outdoors?
Where should I position my outdoor bonsai?
Can I display my outdoor bonsai inside the house? How?
How often should I water my bonsai?
What and when do I feed my bonsai?
What are the best types of plants to use for bonsai?
How, when and why should I repot my bonsai?
What sort of soil should I use for bonsai?
What part does pruning play in bonsai?
When should I prune, and to what extent?
What techniques can I use to wire my bonsai? Is it really necessary?
What books do you recommend for beginners?
What are some good websites on bonsai in general?
I have more questions! Where can I get help?


Is a Bonsai a particular Species of tree?

No. Plainly put, bonsai is the horticultural artform of training plants to look like large, aged trees that appear in nature, but in miniature. Bonsai can be developed from seeds or cuttings, from young trees or from naturally occurring stunted trees taken from woods or elsewhere and transplanted into containers.

A bonsai is not a genetically dwarfed plant and is not kept small by cruelty in any way. In fact, given an adequate supply of water, air, light and nutrients, a properly maintained bonsai should outlive a full size tree of the same species. The techniques of Bonsai are no more cruel than that of any other horticultural endeavour. It is also common belief that bonsai are only a few centimetres tall. This is untrue, although bonsai are small in comparison to their huge life-sized brothers, most are over 25 centimetres tall and up to 1 metre in height.

Most bonsai range in height from 5 centimetres (2 in) to 1 metre (3.33 ft). Bonsai are kept small and trained by pruning branches and roots, by periodic repotting, by pinching off new growth, and by wiring the branches and trunk so that they grow into the desired shape.

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Indoors or Outdoors?

All plants were ment to live outdoors. Some plants manage to live indoors although they still need as much light as possible and more care than if they were living outdoors. Trees are even more difficult to keep indoors and in general most bonsai trees will only live outdoors whilst a few could do well indoors. The first thing you need to know about your tree is its species and then what type of care and conditions it needs to trive.

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Where should I position my outdoor bonsai?

This question is very specific to the species of the bonsai. Generally, try to keep the bonsai out of a position of direct sunlight, where they receive good air circulation, relative humidity, and are in a place where they are easily accessible to you for maintenance (i.e. watering, feeding and pruning).

You can usually tell if a plant likes or dislikes where it is currently positioned. If this is the case, you will detect signs of stress such as wilting, burnt foliage or discoloration and you should move the plant to an area more fitting.

As a general rule, consider the origins of a plant and how it would grow naturally. Plants such as rosemary or the pomegranate for example - which originated in the Mediterranean - are more hardy and thrive in a position of semi shade to full sun, as they are able to withstand drought and appreciate the hot climate.Despite this, it is always best to find out the species of your bonsai and research proper positioning guidelines.

If you want to display your bonsai inside, only do it for a few days at a time.

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Displaying Bonsai Trees Indoors

Yes, you can bring your bonsai inside - but not permanently - and it must be ensured that they are given extra-special attention. Generally you should only keep your bonsai inside for not more than 3 days a month at most. You cannot grow them inside uless they are indoor bonsai which are a completely different group of trees. You may wish to display your bonsai when you are having a special occasion or to admire their beauty when they are flowering or fruiting, but it is not advised to bring them in too often - for risk of causing undue stress to the plant. Care must be taken to ensure that they are given the right amount of water (definitely not allowed to dry out) and sunlight as well as humidity which can be achieved by misting with a general water sprayer.

Make sure that the bonsai are not positioned in the way of any draughts and definitely not next to a heater - even in winter. Above all, the bonsai should not be disturbed too much from their general routine.

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It is very important to frequently water your bonsai. This is mainly because the plants are grown in very small pots, with a very small root system, in a very small amount of soil, and hence can only have very small water reserves, however as in everything extremes are harmful.

In Malta the hot ummer months can be very harsh on bonsai trees and the winter months are often quite low on rainfall so one should constantly watch the trees' condition and water accordingly. there is no set amount of watering that should be done and each tree has its own requirements.

How frequently you water your bonsai depends on many things. A dry wind, excessive heat, or a combination of both, can quickly dry out the soil, so you must monitor moisture levels regularly. Generally if you keep your trees outside where rain can water them, you don't need to worry much in the winter except in times of hot weather or little rain. In the summer you should endeavour to water your plants daily if not more than once a day in very hot periods. Shading the trees lessens their daily water requirements. You may find it is a good idea to set up a drip sprinkler system - where the bonsai are watered every day in the summer and every three days in the winter. Alternatively, you can use a watering can with a fine rose attached to water the soil and roots. Using a general water sprayer to increase humidity is a good idea as is the use of a humidity tray (a tray which keeps a reserve of water underneath the tree's pot - VIP: pots should not be in contact with the water but above it).

On the opposite side of the spectrum, be careful not to over-water your bonsai. This is often a problem of beginners who are over zealous, watering all the time - even in winter - causing the roots to rot. This is also a big problem when keeping succulents (like the Jade Tree) as bonsai as, like cacti, they retain a lot of water and do should not be watered so often.

If you do opt to bring your bonsai inside for a few days to put on display - remember to check the moisture content of the soil daily (just sticking your finger down into the soil should be enough). It is probably wise to take the bonsai outside each day, water it, let it drain, and then bring it back inside. Many beginners keep their newly-bought bonsai inside constantly, and then forget to water it for several weeks. It's hard to comprehend how they can be so surprised when the plant starts turning brown and leaves start falling off.

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To keep your bonsai in good shape and maintain healthy growth requires regular feeding at the right time of year with the correct fertiliser. Fertiliser must be continually replenished due to a certain amount being washed out each time the plant is watered. Since bonsai trees are confined to small pots they need your help to get all the nutrients they need for healty growth

You can get many different types of fertilizers, in a variety of forms. There are slow-release fertilisers which will take care of feeding requirements for several weeks at a time. Soluble powder and liquid feeds are also used for rapid effect over short-term periods. These are applied to the soil with a watering can and are used up relatively quickly.

To understand exactly how your bonsai should be fertilized, you must be able to understand the basic make-up of fertilizers. Most fertilizers contain three basic elements: Nitrogen (N), Phosphorous (P) and Potassium (K).

Nitrogen is an essential ingredient for leaf and stem growth. Too much nitrogen however will make the tree produce long, stringy growth. Phosphorus encourages healthy root growth and helps the growth of new buds, whilst also protecting against disease and unfavorable winter conditions. Potassium (potash) encourages the formation of flowers and fruit, and is vital in the fight against disease.

As a general rule, feed your bonsai from early spring to late summer. One can use most fertilisers available commercially and follow directions however uing half the dose, twice as regularly.It is important to know your tree's requirements and to keep constant look to see what nutrients the tree needs

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Best Trees for Bonsai

Bonsai are tress and therefore trees and not plants should be used to train into bonsai. Most trees can be turned into bonsai trees however there are some trees that are easier than others and some trees which do not trive at all in pots. For a list of trees which Bonsai Culture Group members have managed to train click here.

When choosing a tree to train into a bonsai, think about the climate and the location in which the tree will grow. It's usually a good idea to choose endemic trees and try to make a bonsai out of one of these. You'll find that it's much easier that way and you can gain inspiration from fully grown trees growing locally.

If you bought a bonsai tree from a nursery it is most probably a Ficus, a Zelkova Serrata, a Serissa Foetida a Fukien Tea or a Sageretia Theezans, which are the more common trees available from nurseries.

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Regular repotting is vital to your bonsai's health and growth. It replaces important nutrients, 'stale soil' and allows for new roots. In nature, if trees need additional nutrients, they spread out their roots further in search for more. Bonsai, in small pots, do not have that luxury. Generally, the trees should be repotted at a time when they are most dormant - such as late autumn to early spring, so that they are subjected to the least amount of stress possible. Young or small bonsai require repotting every two or three years, and older and larger specimens less often.

You can tell that a bonsai needs repotting if water takes a long time to drain through the soil or if the roots are crowding around the sides. Sometimes bonsai are so root bound that you can lift them out of the pot and take all of the soil with it.

To repot, carefully lift the tree out of its current pot by tilting it to one side and trying to move it by the base of the trunk. You cannot pull too hard on the trunk - so if this does not work, slide a blade around the edge of the pot or try tapping the pot with the side of your hand to loosen the rootball or poke a stick through the drainage holes and 'push' the rootball out. Next, using a chopstick, knitting needle, metal hook or similar, remove any moss and carefully try to brush and untangle the roots. Start at the edge and gradually work around. Try to 'comb' and 'tug' rather than to 'pull' at the roots - for risk of damaging or tearing some very important main roots. Be especially careful of the white 'feeder roots'.

After this has been done - continue to shake and brush off the soil until about one third to half of the original soil has been removed from the edge and base of the rootball. It would now be a good idea to spray the roots with water to ensure that they do not dry out and so that they will not have too much soil on them when it comes time to pruning the roots.
To prune the roots, use very sharp cutters. There are bonsai root pruning scissors commercially available, however you could just use a normal pair of bonsai clippers or secateurs. If you have washed away most loose soil the scissors will stay sharp, but if they have to cut through soil as well as the roots - they will become blunt very quickly and require sharpening. Start by cutting the thick, old brown roots that have come close to the edge of the pot and are restricting the growth of the young 'feeder roots'. Remove a third to a half of these - being careful that you do not remove too many feeder roots in the process. Next, prune the thinner roots which hang below the depth of the pot by trimming them all into a suitable shape that the pot will accommodate. This should be a shape that fits comfortably into the pot with a 1-2 cm (1/2 to 3/4 in) space between the edges.

The demanding part of the repotting is now over - if you think that you've cut too many feeder roots off, the tree will be disadvantaged but you probably will get away with it - as new roots will grow from the cuts.
Clean the original pot thoroughly or select a new pot that is more suited to the tree and cover the drainage holes with simple wire mesh. As the plant will now be unstable in the new pot as it has nothing to anchor it - we have to make some anchors to prevent the tree from falling over from winds or from being moved. Thread some wire (doesn't need to be very thick) through the drainage holes or specially designed holes for anchoring and leave for later use. Add a thin layer of gravel to aid drainage and then a layer of soil. Moving the tree around, decide a basic position for it (usually off-center and slightly to the back of the pot) and make a small mound that it will sit on.

Now you can place your bonsai on the mound by gently nestling it in and spreading its roots out evenly throughout on top of the soil. Once you are happy with the height and position of your tree (it is going to stay like that for 1-2 years), take the wires that you threaded and twist them together (usually with the aid of pliers) over the main rootball of the tree until it is held firmly (but not too tight) and will not rock. Because these wires are quite unsightly, you can remove them in a few months time once the tree has settled in.

Add more soil up to the base of the trunk - which should be just below the base of the pot. Tap the side of the pot with your hand to ensure that the soil becomes settled and that there are no gaps around the roots. Use your chopstick to incorporate the roots into the soil and to make sure that they are placed correctly.

Once the soil has been applied, you now have the option to add supplementary features such as rocks, moss, accent plants or gravel to enhance the design. When applying moss - be careful that most of the original soil is cut off from the bottom before you plant it and that the moss (or any other plant for that matter) is not too big or vigourous for the pot or tree.

Now you can thoroughly water the tree - being aware that the soil level may settle further and that more soil may have to be added. Place the tree in a position where it will not receive extremes in temperature (i.e. not direct sun) and where it will be able to recuperate. Don't fertilise at this time - as this can burn or cause stress to the plant. You can feed in around a month though, when the roots have recovered.

Note that to balance out the extensive pruning you have just done on the roots, you should prune the branches of the bonsai as well so that it can recover quicker and not be disadvantaged further. Root growth usually does equal branch growth.

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Most beginners use a general potting mix for bonsai soil until they get the hang of things. Ideally the mix is open and free-draining, so you should add gravel and sharp sand (not sea sand). If you can get pre-made bonsai soil use it, however creating your own mix of soil depending on the type of tree and the conditions it grows in will ensure proper growth. At our weekly meetings our members learn how best to mix soils for different species.

Making your own soil mix isn't as hard as you think. A lot of bonsai growers make a bit of an unnecessary fuss about it and almost everyone has their own 'secret formula' but it depends on what plant you are growing. A basic bonsai soil mix to use - and one that would apply to almost all species is: one part loam or local soil (sterilised), two parts peat, two parts grit. All of these ingredients should be easy enough to obtain.

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Pruning is necessary to maintain (or refine) growth to obtain the right shape of a bonsai and encourage new growth. Some plants naturally respond well to pruning, regardless of how intense, whilst other plants can find it hard to recover, especially when pruned at the wrong time of the year. To prune correctly you must find out the type of plant your bonsai is and research when the best times are to prune old and new season growth. Generally, new growth is pruned during the growing season to maintain the shape of the bonsai, whilst pruning of hard wood (old season growth) is done in mid-autumn.

One of the main forms of pruning for bonsai, especially evergreen coniferous bonsai such as junipers and cedars is 'finger pruning'. This involves pinching back new growth which does not come within the general shape of the bonsai or is at the top of the bonsai - helping to encourage bushy foliage and a more tree-like looking bonsai. To do this, take the growth between your thumb and forefinger whilst holding the branch with your other hand and remove with a twisting movement. This is better than trimming the growth with scissors, this leaves an unnatural look and leaves the foliage an unsightly brown.

Leaf pruning (also known as defoliation) in bonsai is used for several deciduous and tropical plants such as ficus or maples to reduce leaf size, remove unsightly leaves and speed-up growth by causing two seasons' growth in one. This is done in the growing season by cutting 60-90% of the leaves off the tree, only leaving a few to ensure that the tree keeps its energy. Remove leaves with fine scissors, cutting them from directly behind the leaf. In the next few weeks make sure that you keep the plant in a hospitable position and climate and supply it adequate water. Remember however, that this form of pruning is only applicable to certain types of plants.

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Not all plants need wiring to achieve their desired shape or to achieve official 'bonsai' status. The Fukien Tea plant for example, can be trained quite easily without the use of wire. Contrary to what many novices may think, wiring of a bonsai is not done to keep the plant small, but rather is a temporary measure used to hold branches in a desired position in order to enhance the shape of a tree. Wire should not be left permanently on a tree and should be checked regularly.

When wiring, try to imitate the natural curves of trees in nature. Make sure that you only attempt to wire branches that are unlikely to break when pressure used to twist the wire around the branch is applied. There are two types of bonsai wire available - copper wire and aluminium wire Both are now available from our club.

The size of wire used depends on the size of branch you want to train and in most part should be chosen yourself - also dependent on how significantly you want to change the shape of a branch and how stubborn the species of plant is. You should purchase wire in a variety of different lengths and test it out on pruned branches from around the garden.

The safest method to use when wiring is by clenching the branch with both hands (not dissimilar to the look of a clamp) and applying the wire by slowly following it around the branch - making sure it does not damage the trunk. Wire the branch first, and then worry about bending the branch (which is made possible by the wire and using the clamp method) to achieve your desired shape. Be careful of leaves or if in autumn, leaf buds. It is always best to anchor the wire so it does actually re-train the branch. This can be done by training the wire up the trunk until it reaches the desired branch, or by anchoring it to another branch. Sometimes, when it is too hard to use large gauge wire in order to train a large branch or trunk, or you don't have the right gauge of wire, you can 'double up' the wiring and wire the branch twice. Another way of training branches is by tying them down with vents or weighing them down with weights.

It is best to not water a day before wiring, and to keep the tree in shade for two weeks after wiring. Check every few weeks for wire cutting into the bark of the bonsai - particularly during spring and summer, or risk the danger of irrepairible scars. It can take many, many years for wire damage to grow out - depending on how serious it is. Deciduous trees are particularly susceptible to wire damage due to large growth spurts in the growing season. One must say however that certain scrars can add charachter to the tree at the same time.