Pruning during late winter in St. Louis is the ideal time for most trees and shrubs and provides a multitude of benefits. Pruning promotes new growth, enhances flower production, and gives woody plants a nice shape. It is also important for maintaining the health of the plant and for most varieties, it should be done annually.
Winter pruning tips:
- Keep your tools clean
- Avoid pruning when it's wet
- Where to begin?
- What not to prune
- What about evergreens?
Keep Your Tools Clean
If you’re planning on pruning your plants yourself, you’ll want to keep your tools clean and sharp so you can make the process happen seamlessly. Remember to spray your tools with a 10% bleach solution between plants to reduce the spread of disease.
Avoid Pruning When It’s Wet
Select a mild, dry day to do your trimming. Moisture in the wounds of woody plant material encourages fungal and bacterial growth. By pruning on a dry day, it allows the tree or shrub to form a callous over the exposed areas after cuts are made.
Where to Begin?
Always start by removing deadwood. If you are unsure which branches are no longer alive, you can do a snap or scratch test. If you scrape a bit of the bark off with your fingernail, you will see green tissue underneath the surface. If there is no green present, the branch is no longer alive. Similarly, dead branches will snap off while live branches will bend giving you a clear indication of what needs to go and what doesn’t. Next, remove crossing branches to thin out the crown of the tree leaving behind the strongest, most healthy branches. This will ensure that the plant receives adequate light and airflow throughout to reduce the incidence of disease. Always cut branches all the way back to the node, or point at which they connect with the next branch. Throughout the process, take a step back and view the tree or shrub from various angles to ensure even shaping. Lastly, remove “suckers” that have sprouted from the base of your tree or shrub. Crape myrtles are notorious for having these.
What NOT To Prune In The Winter
While most plants are best pruned in February, there are some that should not be trimmed in Winter. Spring-blooming trees and shrubs have already formed the buds for the flowers we are all awaiting. Pruning now would remove those and ruin the upcoming show. Additionally, certain types of trees “bleed” at this time of year and are best left until late Spring or early Summer. Maple syrup harvests typically take place at this time for that very reason so be sure to research each type of plant you have before making any cuts.
What About Evergreens?
Not ALL evergreen shrubs require pruning or shearing. Broadleaf evergreen shrubs like boxwood, holly, and privet do well with either option this time of year but trees like Leyland cypress and most junipers do not. Save yourself some time by only trimming evergreens as needed to achieve the size and shape you’d like. If you do not have a formal garden, consider letting your evergreens have a more natural appearance.
