When is the best time of year to prune? There is no correct answer as it depends on the plant and why it is being pruned.
Remove dead and diseased wood as soon as possible, regardless of the season.
Early blooming plants such as; Lilacs, Double Flowering Plum, Nanking Cherry, and Forsythia should be pruned as soon as they are finished flowering. Plants that bloom early set next year’s flower bud soon after their blooms fade.
If flowers are not a concern, prune when the plant is dormant as it is easier to see the plant structure and what to remove.
Tender shrubs which includes roses are easiest to prune once the first leaf buds appear making it easier to differentiate live and dead wood. Roses bloom on first year wood so do not worry about removing flowerbeds.
Prune hedges when they begin to look ragged. Likewise prune plants that are encroaching in sidewalks, windows, roads as needed.
People shy away from pruning as they worry about ruining the shape of the plant. Shrubs are very resilient plants with very few ever dying because they were pruned.
There are a few basic rules of pruning that make it less stressful for the plant. Make sure all cuts are flush with other stems, the ground or just above a bud. Doing otherwise leaves stubs which die from lack of nutrients making it harder for a plant to heal. Open wounds attract insects and diseases.
Prune when the weather is dry. Diseases tend to spread in wet, humid windy conditions.
Sterilize pruning equipment between cuts if the plant is diseased to decrease to decrease the chance of spreading the disease. Burn or double bag the diseased material immediately. Diseased material should go to the landfill not the shredding pile.
Once all the dead material is eliminated, remove all suckers or watersprouts. Suckers sprout from the roots while watersprouts can come from any place on the plant. They are shoots that grow long and straight, without any side shoots in one season. Chances are these shoots will die over winter. Watersprouts are common on shrubs that have been pruned too hard or had a lot of dieback.
Next look for branches that are crossing. Remove one of the crossing branches. Choose the one that is the least healthy or crossing more than one branch. In an old shrub, remove the older branch at the ground level, encouraging the shrub to send up new shoots in the middle of the plant.
The last step is to shape the plant to make it pleasing to the eye. When pruning, keep track of the amount of plant that is being removed. Do not remove more than a quarter of the plant in one growing season. When too many branches are removed, the plant has trouble manufacturing enough food to feed the roots which stresses that plant resulting in watershoots. The rest can be removed over a number of years.
When time permits, remove unattractive seed pods from shrubs as it allows the plant to put more energy into growth as opposed to seed. Leave all attractive berries and seeds intact as it adds to the landscape.
Roses are pruned similar to shrubs.
Using sharp tools, leaving good cuts that will heal quickly will lead to a healthier plant.
Spending a few hours pruning each year adds to the overall appearance of the yard and improves the plant’s health.
Linda Tomlinson is a local horticulturalist that lives near Rocky Mountain House. She can be reached at firstname.lastname@example.org.