why do you need to prune?
Pruning might not be your favourite chore (yet!), but the results are undeniably satisfying. Here's why you should prune most garden plants:
- Pruning spent flowers can encourage second flowering, allowing you to enjoy them for longer.
- Pruning makes for better, healthier growth and more beautiful blooms, with pruning actually encouraging abundant flowering.
- Plants often get too big and/or proliferate if you don't prune them.
- Pruning fruit trees produces more, bigger and sweeter fruit.
- For some plants, such as lavender, pruning ensures they don't become too big and woody.
the basic rules of pruning
An important thing to realise is that when pruning any plant, you create a 'pruning wound'. It takes a while for a plant, shrub or tree to heal this wound, and in light of this, there are some pruning rules that almost always apply:
- Never prune in full summer sun or during a very hot period, as pruning wounds can cause plants to dry out more quickly.
- Never prune during a frosty period. You want to prevent pruning wounds from freezing and branches from dying.
- Never prune when it's raining or on a very wet day. Damp air allows diseases to enter pruning wounds more easily.
- The best time to prune, therefore, is on an overcast day in a dry, non-frosty week when temperatures are relatively mild.
different types of pruning
There are different ways of pruning, including cutting, shape-related pruning and topping. Which type of pruning is best depends on the type of plant and its specific conditions and needs:
- Trimming: cutting off spent branches to extend flowering. This applies to several garden flowers, such as lady's mantle, yarrow, geranium, sweet pea and dahlia.
- Rejuvenation pruning: this type of pruning is necessary for most perennials, hedges and shrubs, as they need to be cut back and/or thinned (either before or after flowering). Dead or diseased branches should also be removed to promote healthy growth. This pruning is seasonal and often takes place in spring and/or autumn.
- Shape pruning: with shape pruning, the aim is to keep plants as compact and dense as possible. You're aiming for no gaps within the plant to allow you to make tight shapes such as a sphere or a spiral. Plants such as holly, yew and boxwood are perfect for this type of pruning. Shape pruning should ideally be done about 3-4 times a year.
- Maintenance pruning: maintenance pruning is a light pruning to promote the health of your plants when you notice it's necessary. Consider removing old, dead parts or branches, generally trimming and deadheading and removing damaged branches. Maintenance pruning is necessary for the healthy growth and beautiful flowering of many plants, shrubs and trees.
- Drastic pruning: for some fast-growing plants or shrubs, such as buddleja, maintenance pruning may not be enough and more drastic pruning is required (about 80-90% of the plant can be away), leaving only the branch system intact.
- Safety pruning: you can think of this as a periodic check of your plants, shrubs and trees after a stormy day or a prolonged period of rain or heat. Remove damaged, diseased and/or stems or branches that are hanging too low, and check your plants for health and safety threats so that they do not pose a risk to themselves, other plants or to you.
- Topping: topping means removing the top part of the plant, allowing it to grow into a bush. The plant will grow less tall and more wide, with side branches forming faster. Topping can be done with pruning shears (for shrubs) or by hand (for young, tender plants). The ideal time to top your plant is usually in spring, just before flowering.
- Pollarding: some trees need more serious pruning, called pollarding. This means cutting branches down to the main tree branch and is done to prevent the tree from growing too big and the branches frm becoming too heavy. It also promotes the production of stems and colourful, large leaves. Trees such as willows need pollarding.
when should you prune? the basic rules
There are no set rules for when to prune, as the best time to prune a plant, hedge, shrub or tree varies by species. Pruning wounds can't heal quickly in winter, so colder periods often aren't the best time for the activity.
To determine the best time to prune a plant, hedge or shrub, look at its flowering period. Roughly speaking, you can apply the following rules:
- Spring-flowering plants: for plants that flower early in the year (before 21 June), prune in the summer after flowering. The flower buds will have already formed last year and will open in spring. Examples: Chinese bell (Forsythia), lilac and jasmine.
- Summer and autumn flowering plants: for plants that flower in summer or autumn (after 21 June), prune in the spring before flowering and when frost is no longer expected (around March/April). These plants usually flower annually, i.e. the flower buds are formed during the spring in which flowering begins. Examples: buddleja, hydrangea and hibiscus.
- Winter flowering plants: plants that flower in winter, such as witch hazel and winter jasmine, can be pruned back into shape after flowering is over.
PRUNING FRUIT TREES
How and when to prune a fruit tree depends on the age of the tree and the type of fruit (whether it's a pome fruit tree or a stone fruit tree). Fruit trees that produce pome fruit such as apple and pear are pruned differently to stone fruit trees, such as plum, cherry, apricot, peach and nut trees.
PRUNING APPLE AND PEAR TREES
- Prune apple and pear trees once or twice a year (in winter and in summer).
- Winter pruning (February/March) is the most important for young trees, because this pruning is growth-stimulating. Summer pruning is more important for older trees, as the growth stimulated by this pruning improves fruit production.
- Young apple and pear trees (ranging from 0-4 years old) should be pruned into shape. Choose a few well-spaced branches that form the 'trunk and prune the rest away. If you want more branches, prune out the top of the tree (the upper branches) to allow enough light and air to reach the crown of the tree.
- Older apple and pear trees (from 4+ years old) need only a light rejuvenating pruning. Remove dead and crossed branches, and make sure the crown remains open. Shorten old, non-fruit bearing branches into a young side branch. Cut the side branches back to about 3 buds/thickenings, and cut them off just above a bud.
PRUNING PLUM TREES, CHERRY TREES AND OTHER STONE FRUITS
- Stone fruit shouldn't be pruned in winter, as these trees are susceptible to mould. Prune stone fruit preferably after harvest in August or September.
- In general, stone fruit trees need less pruning than pome fruit trees.
- Peach trees and apricot trees are best pruned immediately after harvest (August or mid-September at the latest).
- Prune plum trees and cherry trees as little as possible and only if it's necessary for maintenance. Remove any diseased or damaged branches by mid-September, at the latest.
- In principle, nut trees do not need pruning at all. If you want to prune them do it in the autumn, after the harvest.
what should you pay attention to while pruning? handy tips
Looking to prune a shrub, tree or plant into shape? Here's what you should watch out for:
- Always use sharp, clean pruning tools.
- Prune branches at an angle (instead of straight). This helps prevent fungal infections by making it harder for water to get into the pruning wound.
- First, remove dead, damaged and/or diseased branches or stems.
- If you prune a shrub or plant into a shape, make sure to maintain a natural shape. While pruning, look at the plant from a distance and from different angles every so often, so you can observe its shape properly.
- Prune away branches that grow inwards or cross each other. This helps prevent fungal growth.
- For branches thicker than 5 cm, we recommend using loppers or a saw instead of secateurs.
- Cut away branches to just above a bud (also called a thickening or an eye), as this is where new branches will sprout from. You can recognise this spot by the slight thickening of a branch at that point.
- Pruning wounds larger than 10 centimetres will not grow out quickly, so to prevent long-term wounds to your plant, try to prune it before the wounds will be this large. If you have a tree with large branches that need pruning, consider calling in an expert.
- When pruning a tree, prune in moderation and don't remove more than a third of the crown at once.
- Clean and dry pruning tools after use. This is especially important if you have pruned a diseased tree or shrub.
which tools should you use for pruning?
Always prune with clean (so no rust spots) and sharp tools, such as secateurs (for thin and medium-width stems and branches), loppers (for thicker branches on shrubs or trees), an electric or manual saw (for thick branches) or hedge shears (for a large hedge).
Protective gardening gloves and a stepladder can also come in handy. We recommend using a tarpaulin to catch pruning waste so you can dispose of it easily and quickly in your green recycling bin.
how to clean pruning tools
Are there rust spots on your tools? Remove them with a wire brush. Are your pruning tools not sharp enough? Sharpen them or have them sharpened for you. To work as cleanly as possible, clean your tools with disinfecting alcohol after each type of plant - this will prevent the spread of any plant diseases.
how to prune common garden plants
So many plants, so many pruning guidelines, so little time. We recommend researching specific pruning advice for each plant, as there are often different rules for each species and variety. However, if you're looking for general guidelines for common garden plants, check out these tips below:
- Pruning hydrangea: when pruning hydrangeas, it's important to know whether the hydrangea blooms on old wood or on new wood. Check out our hydrangea guide for information and tips on pruning hydrangeas.
- Pruning buddleja: buddleja grows quickly, so pruning is essential. See our buddleja guide for all information on pruning this plant.
- Pruning lavender: lavender will become woody out if you don't prune it. See our lavender guide for tips and information on pruning this plant.
- Pruning lilac: how to prune lilac depends on how old the plant is and what your desires are regarding its size. Check out our lilac plant guide for tips.
- Pruning wisteria: wisteria is one of the fastest growing climbing plants, so proper pruning is essential. See our wisteria guide for information and tips.
- Pruning beech hedge or hornbeams: beech hedge (which keep their leaves and change colour from green to brown) or hornbeams (which drop their leaves in winter) should be pruned twice a year, firstly in May/June, before the longest day (21 June). This will cause new growth to happen. If necessary, you can prune again in September to ensure that the plants go into winter looking neat and that any pruning wounds heal before the frost sets in.
MORE INSPIRATION AND TIPS
If you've finished pruning, you must be curious for more inspiration to make your garden shine brightly. Discover these ready-made plans for a border garden, or check out other ways get greener. If you're ready to head indoors, curl up on the sofa and read all about the latest trends for flowers and plants.
