When and how to prune viburnum bushes – expert tips to keep them in good health

It is important to know how and when to prune your viburnum shrubs because if you cut them back in the wrong season or when conditions are unfavorable you won't get as many flowers and berries the following year and may even damage your plant.

There are many varieties of viburnum, some deciduous (they lose their leaves in the fall) and some evergreen, and the joy of them is they are all low maintenance and easy to keep in shape. They are a very popular flowering shrub because they are one of the few to flower in winter, sprouting small clusters of pink and white blossom, and several including V. burkwoodii and V. opulus also produce a beautiful scent.

I have a large Viburnum tinus that we inherited when we moved into our home several years ago and the techniques I use to keep it in shape apply to all varieties, so if you follow my advice you will end up with a healthy, shapely shrub with prolific flowers.

Ruth Hayes

As the gardening editor of Amateur Gardening magazine, Ruth spends her days writing about and photographing the gardening jobs that her readers should be tackling each week. Horticulturally trained, she has qualifications from the Royal Horticultural Society. Pruning is one of the key tasks she offers advice on in the weekly magazine, showing readers how they can keep their trees and shrubs, such as viburnum, in shape. 

When to prune viburnum

As a general rule, viburnums are pruned after they have flowered. They are robust deciduous and evergreen shrubs and produce flowers any time during the winter months, sometimes blooming right up until June.

The flowers start as tight clumps of small round buds on the end of stems, and gradually open into attractive clusters of small blooms. The variety V. tinus 'Gwenllian' produces flowers and berries at the same time.

While most viburnums are given a trim after flowering, if you have a variety that produces berries, such as Viburnum davidii or Viburnum lantana, wait to prune until the fruits start to shrivel and drop in the fall.

When to avoid pruning viburnum

Viburnums flower on wood produced the previous year, so if you prune them in early spring or late winter all you will do is remove the growth that is preparing to burst into blossom.

The best time to cut them back is just after they have flowered, or in the fall when berrying varieties are dropping their fruits.

Pruning should also be avoided when the weather is very cold and there is lingering frost and snow because severe cold can scorch pruning wounds, blackening the shoot tips. If you prune in freezing weather, the shock may stunt growth and even kill the plant.

Also avoid pruning viburnums growing in the soil after heavy rainfall. The ground may be waterlogged and walking on it will compact it, driving out the oxygen and potentially damaging the shrub's roots.

How to prune viburnum shrubs in 3 easy steps

Whether your viburnum is a deciduous variety such as Viburnum carlesii and Viburnum x burkwoodii, or evergreen like Viburnum tinus and V. cinnamomifolium (cinnamon viburnum), they all have the same pruning regime.

1. Remove any dead, damaged and diseased wood

The first step with any pruning regime is to remove the ‘three Ds’ – wood that is dead, damaged and diseased.

You should also add to this list any wood that is weak, spindly and growing inwards into the bush, cluttering its interior and blocking healthy airflow and sunlight that is essential for good growth and flowers.

Old, dead wood can be tough to remove and too strong for pruners to work through, so my tools of choice are long-handled loppers, such as these Fiskars ones on Amazon (opens in new tab), that are ideal for reaching high-up wood, and a sharp folding pruning saw, also from Amazon (opens in new tab), with a comfortable grip.

Once these unwanted branches have been removed, I chop them up small or shred them in a wood shredder, like this Sun Joe one from Amazon (opens in new tab), which is a useful, time-saving tool if you have lots of wood to get rid of. 

You can then either use the chippings as a type of mulch or use them as a valuable ingredient when making compost.

Before you start pruning the rest of your viburnum, remember the old saying ‘look twice and cut once’ – an invaluable way of reminding yourself not to take off too much wood because once it’s removed you can’t put it back! Following the one third pruning rule can help you avoid removing too much too.  

2. Remove dead flowers

Annual viburnum pruning is simple because all you need is to snip away the spent blossoms using sharp, clean pruners such as these from Amazon (opens in new tab), cutting the stems back to a healthy leaf node or bud. 

This will encourage the plant to produce new growth that will harden and mature over the next few months and bear blossom next spring.

Look for signs of pests and disease, and if you spot diseased wood, cut it back to healthy growth and dispose of the clippings in your bin – never add them to the compost heap.

Make sure you clean your garden tools after use to prevent them rusting, and to help stop the spread of pest and disease.

3. Cut away old and unproductive wood

Remove thicker stems that have grown lanky and unshapely and stopped flowering reliably.

Use loppers or a pruning saw to remove them but don’t take too many in one go as it can leave the shrub unbalanced. Instead, wait until the same time next year to remove more.

Don’t cut branches flush against the trunk, but leave a little stub about 1in long so a healing callus can form naturally.

Viburnum pruning aftercare

Viburnums don’t require much after-care following pruning, but I do recommend you feed them with a tree and shrub fertilizer such as this BioAdvanced one on Amazon (opens in new tab) to help them make the most of their growing season ahead. 

Water it in following the manufacturer's guidance. Mulching after this will hold in the moisture and add nutrients to the root area.