Pruning Can Do Harm
If you trim trees and shrubs in the fall, you will end up stimulating growth just before your plants get ready to go dormant. This, in turn, makes the plants weaker. When you prune on a warm day, sap starts to rise in the plant. When the temperature drops below freezing, the plant suffers and can even die.
Pruning is best left to early spring or the tail end of winter. Give your plants a haircut then. Most gardeners err by over-pruning bushes and trees pre-winter, leaving their plants vulnerable to the stresses of winter temperatures, pests and disease.
For lilacs and spireas that bloom in early spring, prune them after they finish blooming. The only exceptions for pruning at the end of fall and start of winter are deciduous shrubs that are overgrown.
Also, remember to not prune when it is wet outside. This can spread diseases through the growth of microbes that take advantage of the weak state your plants are in. Instead, wait to prune when the sun is out for a period of time to dry out and kill bacteria and mold.
When the Time is Right, How to Prune
When you do have to prune, first remove dead and dying branches from the body of the plants. If branches are rubbing each other, prune to allow for healthy growth.
Plants that can be pruned just before the start of spring include glossy abelia, beauty berries, hydrangeas, Bradford and Callory pears, crabapples, poplar, spruce, junipers, sumacs, cherries and plums. Maples, birches, dogwoods, walnuts, and elm tree should be pruned only after spring has started to prevent sap from oozing out of the trees and weakening them.
Remember to keep your pruning shears clean to prevent disease from spreading accidentally. Simply wash tools with a teaspoon of bleach in warm water and then allow to dry.
Fall Maintenance Tip: Install Rain Gutter Guards
One of the most important steps of fall garden maintenance is to clean out your gutters and make sure you have rain gutter guards installed and functioning properly. A gutter leaf guard helps protect your gutters from debris and plant material accumulating in your gutters, thus allowing the steady natural flow of water down the roof, through the gutters and to the ground. With properly installed rain gutter guards, you can keep your gutters clean and protect your home from water damage that happens when water does not flow properly away from the house.