Unlike trees, deciduous shrubs do not require formative pruning. These plants generally need very little annual pruning. In most cases, simple maintenance pruning (once a year or even every two years) is enough, with occasional rejuvenation pruning when needed.
How to Perform Annual Maintenance Pruning on Shrubs in Eastern Canada
Pruning shrubs is a simple but important task that helps maintain plant health and structure.
Shrubs in your garden will benefit from regular maintenance pruning. This technique is easy to apply and accessible to gardeners of all experience levels. With a good pair of clean, sharp pruning shears, follow these basic guidelines:
- Remove dead, diseased, or damaged branches;
- Remove branches growing inward toward the centre of the shrub;
- Cut back weak or poorly positioned growth;
- Shorten branches that disrupt the plant’s natural shape.
What About Spent Flowers: Should You Deadhead?
Some gardeners dislike the look of spent flowers and remove them as soon as blooms begin to fade. A long-standing belief suggests that deadheading improves plant health and encourages more abundant flowering the following year.
This was true for older annual varieties before the introduction of modern continuous-bloom cultivars, and it still applies to some perennials. However, for shrubs, research does not support this practice—removing spent flowers does not increase flowering the following season.
While less visually appealing at first, these branches often provide a second season of interest, producing colourful and sometimes edible fruits.
In Eastern Canada and beyond, the fruits and seeds produced by shrubs are an important food source for wildlife, especially birds. Encouraging this natural food supply in your garden is a simple way to support biodiversity. It also allows you to enjoy a greater diversity of birds throughout the seasons—making spent flowers far less of a concern.
Different Types of Pruning for Shrubs
Rejuvenation Pruning: Restoring Vigour Over Time
Over time, shrubs may lose their shape, become bare at the base, or develop dense, tangled growth. In these cases, rejuvenation pruning can help restore vigour and extend the plant’s lifespan.
Gradual Rejuvenation for Long-Term Health
To maintain shrubs over many years, it is beneficial to periodically remove up to 30% of the oldest wood. For multi-stem shrubs such as ninebark (Physocarpus opulifolius), stems should be cut at ground level. For single-trunk species such as pagoda dogwood (Cornus alternifolia), cuts should be made at the junction of the current year’s growth.
This pruning should be done periodically rather than every year. Some gardeners use leap years as a simple reminder.
Coppicing: A More Intensive Rejuvenation Method
Coppicing involves cutting all stems back to about 10 to 15 cm above ground level. This technique is useful when shrubs have been neglected or have become difficult to manage.
It can also be used intentionally to enhance ornamental features. Hard pruning can intensify stem or foliage colour and encourage more uniform flowering in species that bloom on new wood.
However, for shrubs that flower on old wood, coppicing will eliminate flowering the following year. In some cases, this trade-off may still be worthwhile.
Coppicing is generally used in two situations:
- To restore overgrown or aging shrubs;
- To enhance ornamental traits such as stem colour, foliage, or flowering.
In these cases, it can become part of a regular maintenance routine.
It is recommended to apply compost or fertilizer at the beginning of the growing season after coppicing.
WARNING: Coppicing is not suitable for all shrub species.
Suitable species are those capable of producing vigorous new shoots from the base. Examples include red-osier dogwood, shrubby cinquefoil, ninebark, shrub willows, spirea, common lilac, and American elderberry. When in doubt, consult a professional.
When Should You Prune Shrubs in Eastern Canada?
For maintenance pruning, timing depends mainly on the plant’s flowering habit.
- Prune in early spring, before bud break, for species that flower on new wood (such as summer-flowering shrubs like shrubby cinquefoil or spirea);
- Prune immediately after flowering for species that bloom on old wood (such as spring-flowering shrubs like lilac). Avoid removing too many flowering branches, as this can reduce fruit and seed production.
For coppicing, the ideal time is early spring before bud break. It can also be done in fall for very hardy species.
Dead, damaged, or diseased branches should be removed as soon as they are noticed, regardless of the season. The same applies to suckers and basal shoots.
Additional Practical Tips
Wound sealants are unnecessary in most cases.
Hedge trimmers may be useful in certain situations, but hand pruners are generally preferred for precise, selective cuts.
During the first years after planting, annual maintenance pruning helps strengthen and densify shrubs. This step is important for establishing vigorous, well-structured plants.
