October usually starts out very warm and begins to cool slightly towards the end of the month. Do a hard pruning on anything that needs it by mid-October. You can do minor trimming and shaping at any time of year but if you cut anything back hard, it’ll need time to grow a bit before any winter cold snaps.
Fertilize any plants that are not performing as desired. This is the last month of the year to fertilize shrubs and trees, you can use controlled-release fertilizers to provide nutrients over a longer period of time