Keep on Watering
Keep watering trees and shrubs that were newly planted this growing season until the weather turns really cold and the ground freezes. Even established planting may benefit from a good soaking after our dry summer if fall rains are sparse. Although the tops of woody plants may be dormant, their roots are still active until late in the season. Give all evergreens a good soaking just before the ground freezes to help them come through the winter in good condition.
Dig and Store Dahlias
When frost blackens the tops of dahlias, cut the blackened foliage back to 2 inches, then carefully dig up the tubers. Let them dry for a few days, brush off any loose dirt and store in a cardboard box lined with perforated plastic and filled with dry peat moss, wood shavings, styrofoam packing peanuts or other similar material. Nestle the tubers in the filler stem side up and not touching. Store in a cool, dark spot, ideally between 35-45 degrees F.
Weed One Last Time
Give your perennial gardens and shrub beds a thorough weeding in the fall and you'll have fewer weed problems the following year. It's also a good time to edge beds. Gardens will look neater and there will be one less chore to attend to during next spring's busy season
Cut Back Woody Subshrubs
Prune back Russian sage, sage and lavender to about 6 inches if you want to neaten up the garden. Don't cut these woody subshrubs back to the ground.
Prepare Barriers for Evergreens
The foliage of evergreens such as rhododendrons and dwarf Alberta spruce can be injured over the winter by the drying effects of wind and sun, especially if they are planted in a southern or western exposure. Protect plants over the winter with burlap screens. Although you can wait until the really cold weather hits in late fall to put up the burlap, drive in the stakes to which you'll attach it now while the ground is still workable.