A steady temperature rather than one which fluctuates a lot is highly recommended, so avoid draughts, or placing your bonsai on top of a shelf with a radiator underneath. 

Bonsais need as much natural daylight as possible but avoid direct sunlight which can scorch the leaves and speed up the water evaporation from the compost.

Your bonsai needs regular watering; it needs to be moist but not overly wet. The best method is to completely immerse the pot in water so the water level is above the soil. Wait until all the air bubbles have stopped rising, then place the pot on a drip tray. Water which drains off will evaporate and keep the foliage in a humid state. The warmer the room the more often you may need to water your bonsai. It could be once a day or once a week depending on the location. Test the surface of the compost; if it is moist wait a day or so then test again. Do not let your bonsai dry out completely or stand in water for long periods.

Bonsais will benefit from regular misting (two to three times a week) especially in winter with the central heating on. You can spray with soft water or use Bonsai Myst which will provide nutrients at the same time.

Water your bonsai before you feed to avoid root burn. It is advisable to use a proprietary bonsai fertiliser such as Bonsai Focus which is highly recommended. This will help the tree to get the required nutrients for healthy growth. Feed once every one to two weeks throughout the year and avoid feeding in November to January. For bonsai azaleas or other acid-loving plants, it is preferable to use Camellia Focus.

It is important to regularly trim your bonsai to keep its shape or style. This is called the ‘clip and grow’ method. When a new shoot has elongated and has between six and eight new leaves, it should be trimmed back to two to four leaves. This may be every two months or so depending on the vigour of the tree. With regular pinching back the tree will fill out better. A pair of pruning scissors such as Growth Technology’s Bonsai Pruning Scissors are very suitable.

Alternatively, you can use the wiring method. You can use anodized aluminium or copper wire which has been annealed. The wire comes in various sizes from 0.5 to 6.00 mm in diameter. The wire is wrapped around the trunk or branch then bent into the shape your styling requires.

Indoor bonsai are best repotted in the spring every two years. Top pruning can be carried out after repotting. As well as a good quality repotting mix such as Bonsai Focus Repotting Mix Peat Free, you will need a pair of pruning scissors, a hook, mesh, wire and a container of the appropriate size to accommodate two year’s growth.

Put on a pair of gloves and rework the mix so it regains its texture. For a more free-draining mix add 10% horticultural grit.

Cut any wires and carefully ease the plant from the old container. Loosen the root ball and remove all the soil that you easily can with a chopstick or a root hook.

Add SuperDrive to the water to encourage vigorous rooting. Cutaway dead roots and trim off about thirty percent of them, especially the thick ones.

Cover the drainage holes in the new container with mesh and hold it in place using anodised aluminium bonsai wire. Insert wire for tying in the tree.

Add a layer of mix to the bottom of the container. Hold the bonsai in place and tie the wires around major roots or base of the trunk, to secure the bonsai into the pot. Add more mix and work it very well in between the roots using a chopstick or similar tool, leaving no air pockets.

Work mix between the roots, and fill the container. Water well from the top until there is runoff. Keep in the shade for three weeks to allow new roots to grow. Start feeding with Bonsai Focus four weeks after repotting – it will encourage healthy, bushy growth and prevent leaf yellowing.

For a video on how to repot indoor or outdoor bonsai as well as many types of orchids please click here.

Yellow or fallen leaves

If your bonsai starts to show a change of colour, with leaves turning yellow, do not be alarmed. This could be due to a number of reasons such as a shock to the tree caused by being very dry or very cold. If any of these have occurred, adjust the environment.

Depending on the species, fallen leaves could be a natural occurrence. The tree is not dead, but just going into temporary dormancy, so be extra careful with watering. Fallen leaves will be replaced by a new set of leaves four to eight weeks later.

Fungal diseases

Bonsai trees can be subject to fungal problems just like trees in nature. As soon as you notice problems use an appropriate fungicide and follow the instructions on the label. SB Plant Invigorator is highly recommended for mildew and it is widely used preventatively.

White ‘threads’ on the leaves

White fluffy insects in the plant crevices

These are most likely mealybugs. Remove with a cotton bud dipped in methylated spirit and wipe the leaves clean regularly to prevent an infestation. Additionally, spray with SB Plant Invigorator as per the instructions on the label. After the first signs spray at least twice a week for two weeks to kill off any remaining insects.

Leaves curling

This normally indicates either aphids, coddling moth grub or even a spider’s nest. Check inside the leaves and spray with SB Plant Invigorator.

Water does not drain through the pot

This is usually because the growing substrate has degraded and it indicates the need for repotting.

Roots are coming out the drainage holes or the tree is lifting out of the pot

This indicates the need to repot the bonsai and trim the main root.

Brown tips on leaf edges

This is likely to be caused either by sun scorching the leaf tips or soil drying out. Move to a shady position and/or water regularly.

Long, leggy growth

This is usually due to lack of light and new growth. New growth is drawn towards where light is. Move to a brighter position.

For advice on outdoor bonsai please click here for information on this subject.