The approach to our tasks for winter in Western Australia is different to what you would read of in publications such as "Bonsai Today". Due to our geographical differences things have to be done a little differently.
If followed correctly, the steps below will ensure your plants are well prepared for winter, and some of the things you may have found necessary to do in the Spring will be unnecessary.
Remove the soil in the top of your pot to a fdepth of approximately 1cm, or at least to the top of the root ball. This is done for a couple of reasons. By removing the leftover topsoil you remove any leftover fertilizers, which can cause clogging of the soil and could prevent adequate aeration. Additionally un-germinated seeds, that may be lying dormant in preparation for the spring, are eliminated, saving a time consuming job. Replace all soil with some suitable fresh bonsai soil.
Carefully push a thin bamboo skewer (or similar object) right through the soil to the bottom of the pot, (repeat this at spacing of about 2cm all over the surface of the pot).