Hints on the care of your Bonsai
 

During the growing season (April to September inclusive in the northern hemisphere antipodeans please add or subtract six months) inspect the compost daily and water as needed. This will be a daily need when the weather is really warm. For the rest of the year, just make sure that it doesn’t dry out completely. A fortnightly liquid feed at around half strength is beneficial when there is actual growth taking place.
If your tree has been styled already, it is necessary to trim new growth to keep the style and shape from getting out of hand. This can be achieved by allowing the formation of around five new leaves or buds to develop and then trim back to just above the second or first new bud. This choice allows you to select the one which points outwards or downwards for new extension which will create a better shape each time you do it.

In spring, just as the first signs of buds swelling are seen, it is usual to re-pot your tree. Not, as is the usual practice with potted plants, into a larger container but back into the same one with fresh compost. This is the process which dwarfs the tree and makes it look like a mature specimen in miniature. To make room for the new compost it is usual to cut away some of the roots. Up to one third is quite safe, taking away any coarse or tap roots which may have formed. The fine fibrous roots are the ones which do the feeding anyway. The only function of the long coarse ones is to anchor the tree in the ground. It is not considered adviseable to prune the roots of Larch after new green growth has appeared so they should be the first specie on the list for a re-pot. If they start growing before one starts re-potting, it is best to leave them for the following late winter.
A useful mixture for compost, which should always be free draining is equal parts by volume (not weight) of John Innes no.2, sieved composted bark and coarse grit. There are many personal ideas about compost mixes but you’ll not go wrong with the above. This may be modified for specific needs, for instance, by increasing the portion of grit for pine or increasing the bark and reducing the John Innes for lime intolerant species.
There is no such thing as an ‘indoor’ tree and your’s should spend most of it’s time outside. The occasional time indoors (no more than three days) is nice if you wish to show it off to visitors. The exceptions being those trees from warm climes which may need protection from low temperatures.

It is helpful to mention at this point that evergreen, needle bearing trees are better left until May for re-potting. They may be done at any time during the comparatively inactive cold months, as some of us, with a lot of trees to look after, have to spread out this time consuming activity. Pruning of these can differ according to species so ask here if in need of guidance.