1. Do my ornamental grasses need dividing?
2. Do my hostas need dividing?
Late fall is the best time to do #1 and #2 above, so determine if you should do this now and where the new plants will go so that you will be ready to do it next month.
3. Your summer flowering perennials – if they have finished flowering, cut them back to the green leaves and watch them flower again to get you thru fall with some colour.
5. Evaluate your summer containers. Is there a plant that is dying out? Remove it and add a fall annual to extend the season. Kale is a great choice for cooler temperatures.