What to Prune, When to Prune

1. Choose the Right Time

There isn’t a single best time for pruning, it depends on the plant. Here are our pointers for when different types of plants prefer to be pruned:

• Late winter is an ideal time for pruning deciduous trees and shrubs, roses and grape vines, because they're dormant (and leafless). This means it's easier to see what needs to be pruned and it reduces stress on the plant. Late-winter pruning promotes fast regrowth in spring

• Some trees, like maples, birches, and magnolias, bleed sap heavily if pruned in late winter. This doesn't cause them too much harm, but you can avoid it by pruning these trees after they're fully leafed out in late spring, or early summer

• Prune spring-flowering trees and shrubs right after they finish flowering, at the end of spring. If you prune them in winter, you'll cut off their flowers before they get a chance to bloom

• Trees and shrubs that bloom during summer and into autumn are best pruned in later winter or early spring, as soon as their annual growth begins

• In general, avoid autumn pruning because it stimulates tender new growth, that risks being killed by frosts in winter

• There are a few pruning targets on the hitlist that can be pruned any time (as soon as you spot them): suckers; water sprouts; or branches that are dead, diseased, or damaged. Check the diagram below for what to look for

• Summer is the easiest time to remove dead branches, when they stand out against the leafy branches

• Always choose a clear, still, dry day for pruning (it reduces the risk of fungal diseases infecting the fresh pruning cuts)

We've kept these pruning tips concise, but if you'd like to dive into lots more detail, have a look here for our in-depth introduction to pruning.

2. Cut in the Right Place

The standard method for pruning roses, fruit trees and berries is to make pruning cuts just above an outward-facing bud, as in the picture below. This technique triggers the plant to produce new growth from the bud (this is called a heading cut). Angle your cut at 45°, so water runs off the cut.

On the other hand, if you cut right back to where the branch meets the trunk or main stem, it doesn't encourage new growth, so it's the method to use for thinning out a plant (and it's actually called a thinning cut).

• To make a thinning cut with secateurs, hold the thinner, upper cutting blade nearer to the trunk or main stem, then make a clean cut without tearing the bark.

• Don't leave a stub, which will encourage unwanted growth, plus provide an entry point for pests and diseases.

• Cut just outside the branch collar, the swelling where the branch joins the main stem or trunk (see the diagram below). This improves the plant's natural healing response and reduces stress.

• It's recommended to use the '4-cut method' to cut large or heavy branches, to avoid damaging bark - follow the steps 1-4 in the diagram.

3. Choose the Right Tool

Always use clean, sharp tools. Select the right-size tool for the branch you're pruning, to avoid damage to the plant and the tool.

• Secateurs or pruning shears work best on the smallest branches (bypass-type secateurs make the neatest cuts and won’t cause crush damage).

• Use loppers on branches 2 – 3cm in diameter.

• Use a pruning saw on branches larger than 4 – 6cm in diameter.

Tool Tips

• The most versatile pruning tool is a good-quality pair of secateurs. Get the best you can afford, you won't regret it! Wrap some brightly-coloured electrical tape around the handle, so they'll be visible even if they're half-buried in mulch.

• A good pruning saw, with a narrow blade that can be maneuvered into crowded parts of the plant is a valuable addition to your tool collection.

• For trimming crisp, formal hedges you really need sharp hedge clippers. But if this sounds like too much hard work, electric or battery-powered shears are a real labour-saver.

• Don’t forget a stout pair of gloves – especially for rose pruning!

Stay Safe: Smart Precautions

• A hat for sun protection is ideal, but make sure it doesn’t obscure your vision so you don't get poked in the eye, or bash your head on a branch

• If you need to prune a tree from a ladder, tie it securely to the tree when you get to the top. Arrange for someone on the ground to hold the ladder and keep an eye on you. Keep a grip with one hand on the ladder, while you use a pruning saw. Wear shoes with good grip!

• Keep tools sharp, clean and lubricated. Storing tools in protective covers is really good practice for safety and longevity

• It's easy to get poked and scratched pruning trees and shrubs, so wear safety glasses, long pants, long-sleeved shirt and gloves

• Choose a clear, dry day to do pruning. Plant foliage and footing won't be wet and slippery, plus you have better visibility

• Carry pruning tools with the points facing down and away from you

Tool Hygiene

If you're working with diseased plants, it's important to clean secateurs and other pruning tools between each plant to avoid spreading bacteria or spores between them.

• Clean tools by wiping the blades with methylated spirits, bleach, or alcohol wipes, then rinse with water.

• Dry off with a rag, then spray a light coat of penetrating oil onto the blades to prevent rust.

As part of the pruning process, clean up any leaf litter from under trees (especially fruit trees). The dead leaves can contain fungus spores and overwintering insect pests, so they should be removed and burned.

Why Should I Prune? Common Reasons:

• To preserve the shape of the plant (to keep it attractive, or for practical reasons like being able to reach fruit)

• To restrict the size of the plant (although it's always better to choose a plant that fits the space, rather than being forced to constantly prune)

• To encourage productive growth (e.g. flowering shoots on roses, or 'fruiting wood' on orchard fruit trees)

• To remove 'dead wood'

• To rejuvenate an old, declining plant (hard pruning or 'skeletonising' can turn back the clock for many plants)

• To remove old canes from the base (for plants like berries and abelia)

• To thin out a tree canopy and allow air movement through branches - this reduces disease risk

• To form plants into special shapes, like topiary, standards or espaliers

• To encourage colourful new growth (e.g. vibrant new red leaves on photinia)

• To maintain and tidy a hedge or screen

• To discourage vertical growth on plants and encourage sideways branching

• To thin out crowded growth, for better fruit or flowers

• To remove 'suckers' springing up from the rootstock of grafted plants (they quickly take over, but won't deliver the fruit or flowers you want)

• To deadhead spent flowers, which encourages new blooms to form