The weather is still very warm, so you may continue fertilising until the end of April with a high potassium fertiliser for all bonsai except natives, as this will assist in preventing winter die back in flowering trees, maples and elms. If the weather suddenly turns cool you can reduce or even cease fertilising as a trees’ growth will naturally taper off.
Any deciduous trees should be exposed to more sun to ensure good autumn colour – although not if temperatures remain over 30?, otherwise you will end up with brown tips or whole leaves burnt instead of beautiful autumn colour. Don’t forget that the sun is the catalyst for plant health and vigor so now is the time to think about rearranging your benches to provide maximum exposure during winter. Make sure you rotate plants on a regular basis to expose all sides equally to the sun.
Repot natives during autumn and continue repotting evergreen trees whilst weather is warm. If it becomes cold just after repotting, just make sure the trees are placed somewhere warm at night for a couple of weeks.
Keep weeding! They take nutrients from the soil and may also encourage disease to attack your bonsai. Why do these pesky plants grow so well and in such profusion while we struggle to grow a tree?
As we move towards winter trees begin to lose their vigour and so now is a great time for wiring as the wire can be left on for longer periods without fear of damage to the trunk or branch by the wire cutting in.
You can begin to pluck out unwanted and older needles on pines to improve light and airflow to the branches. The same applies to conifers such as picea, cedar and junipers where foliage pads and needles can be thinned and brown needles removed.
For those of you who are entering the Bonsai Section of the Royal Easter Show, and hopefully there are many of you, best of luck!!