How to Prune Hydrangeas

The Ultimate Guide to Pruning Hydrangeas so You Get More Blooms

Part of our Hydrangea Growing Guide by Daniel Woodley at DIY Gardening

If you’re new to growing hydrangeas or you’re an old hand that’s come across an issue with pruning, let us help you master this process with our easy-follow guide.

The good news is that if you follow the steps in this guide, your hydrangea will grow strong, healthy and full of colourful blooms each and every year.

We’ve already covered why hydrangeas don’t flower, but as pruning mishaps are the number one reason, we felt it was time to create an entire guide to pruning.

Danny Woodley

Daniel Woodley

Find Out Which Hydrangea You Have

Some hydrangeas perform best when pruned lightly and won’t tolerate pruning mishaps; they may even refuse to produce any blooms until the following year. Others prefer aggressive pruning and can look leggy and sparse unless pruned hard.

Don’t worry if this all sounds confusing; our guide is easy to follow and guarantees success.

Hydrangeas can be split into five categories, and they are all pruned differently:

Hydrangea Macrophylla – also known as the “big leaf” variety. There are three types of macrophylla; lacecaps, mopheads and mountains.

Oakleaf – the only hydrangea that produces leaves similar in shape to oak leaves, just bigger.

Paniculata – long panicles containing clusters of flowers make this hydrangea distinct and easy to identify.

Aborescens – large leaves and large globe-like flowers make this hydrangea stand out from the crowd.

Climbing – the only hydrangea to climb, and it can reach 20 metres. It produces small clusters of lacecap flowers, usually white.

Here are some photos to help you identify your hydrangea:

Free hydrangea photos

Hydrangea macrophylla mophead

Hydrangea lacecap

Hydrangea macrophylla lacecap

Mountain hydrangea

Mountain hydrangea

White hydrangea paniculata flowering

Hydrangea paniculata

Large globe containing small overlapping petals

Hydrangea aborescens

Aborescens from a wider angle

Aborescens from a wider angle

Oakleaf hydrangea

Oakleaf hydrangea

oak leaf hydrangea leaves

Oak leaf hydrangea leaves closeup

Climbing hydrangea flower

Climbing hydrangea

How to Prune Hydrangeas

Before you read our guide to pruning hydrangeas, it’s important to understand that some species will produce blooms via buds that formed the previous year.

This type of hydrangea blooms on “old wood”, and the buds are set in autumn; if they survive the winter frost and aren’t inadvertently chopped off, they will form flowers the following summer.

Frost and pruning mishaps are the most common reasons hydrangeas won’t flower, so the gardener should be careful not to prune the “old wood” hydrangeas aggressively.

When to Prune:
Macrophylla (Mopheads & Lacecaps)
Two methods: In spring after frosts or immediately after blooms fade in summer, before next years buds have been set.
Oakleaf hydrangea
Two possible methods: In spring after frosts or immediately after blooms fade in summer, before next years buds have been set.
Paniculata hydrangea
Early spring.
Arborescens hydrangea
Early spring.
Climbing hydrangea
Late summer after blooms fade.
Flowers on:
Macrophylla (Mopheads & Lacecaps)
Old wood
Oakleaf hydrangea
Old wood
Paniculata hydrangea
New wood
Arborescens hydrangea
New wood
Climbing hydrangea
Old wood
Method:
Macrophylla (Mopheads & Lacecaps)
Doesn't require yearly pruning but you can prune off up to 20% of stems just above the crown in spring as this encourages new stems from the base, these will flower in the second year. Leave old blooms on over winter for frost protection and cut them off at the nearest set of buds after the last spring frosts but be aware that the deeper you prune a stem, the more buds you'll remove and the fewer flowers that will appear. Alternatively, prune in summer after the blooms fade and before the plant sets buds for next year.
Oakleaf hydrangea
Often requires less pruning. Cut off old blooms to nearest set of healthy buds. Remove up to 20% of old stems just above ground level to encourage new growth if required.
Paniculata hydrangea
Either cut back leaving 2-3 sets of buds on the previous year's growth or prune entire shrub back close to the framework (the thickest stems), leaving some buds on the stems. Ideally, remove about 30-50% of the plant and all skinny or weak stems, leaving a framework of thicker stems.
Arborescens hydrangea
Prune hard, 25cm from the ground to promote fewer but larger blooms or prune lightly to a framework 50cm from the ground to encourage more but smaller blooms.
Climbing hydrangea
Prune in summer after blooms have faded and before new buds form. Cut out overly long and wayward stems to desired length or to nearest large stem/branch.
Warnings:
Macrophylla (Mopheads & Lacecaps)
If you prune a stem by more than half, it's unlikely to produce blooms for the season but will in the second year. Or it may produce small blooms which are smoothered by leaves on longer, newer stems. Alternatively, prune after the blooms fade in summer and before the plant has set buds for next year. Be aware that in some climates, the old faded blooms offer winter protection from frost, hence why some gardeners leave them on over winter. If you cut off buds, or they are damaged by frost, then it won't bloom in the coming season.
Oakleaf hydrangea
As above.
Paniculata hydrangea
Can cope with more aggressive pruning. If pruned lightly, panicles will be more numerous but noticably smaller.
Arborescens hydrangea
Can cope with more aggressive pruning and is more forgiving.
Climbing hydrangea
To control a large wayward climber, consider twice yearly pruning to gradually bring it under control, leaving at least some buds for blooms.

When to Prune Hydrangea Macrophylla

Hydrangea macrophylla is the shrub that gardeners have the most issues with as it blooms on old wood and isn’t frost resistant.

There are several schools of thought as to how best to prune macrophyllas but one should remember that they don’t always need pruning, for most macrophyllas, it’s optional.

1) Prune immediately after the blooms fade in the summer and well before the plant sets buds for next year’s flowers. This option removes the frost protection that the old blooms would offer if they were left on the plant over winter. However, the gardener is less likely to chop off buds as the plant hasn’t set them yet.

2) Prune lightly in spring after the last frosts. By leaving the old blooms on over winter, the plant will have some frost protection, but aggressive pruning will remove the buds that were set last year, and no flowers will form. This method is more suited to very light pruning and deadheading. If you prune hard in spring, it’s very likely you’ll chop off most of the buds needed for the blooms. Light pruning can be defined as deadheading, trimming off frost-damaged stem tips and pruning out thin, weak stems.

3) As above but remove 10-30% of the stems from the crown of the plant. This method is a great way of reducing the size of a large, wayward hydrangea as it will still flower on the remaining stems whilst producing new stems from the base that will flower the following year and improve density. This method should be repeated for a few years until the hydrangea is at the desired size.

4) Remove all the stems at ground level or just above the crown of the plant in spring. Macrophyllas won’t flower on new growth this year, so this method means no blooms will appear until the following year, but this is the quickest method to get a large, wayward hydrangea down in size.

Note: Climbing hydrangeas should be pruned in summer after the blooms have faded.

Our Advice on When to Prune Hydrangea Macrophylla

If you want to prune your hydrangea macrophylla very lightly, i.e. deadheading and removing thin, weak stems etc., then leave the old blooms on for frost protection over winter and prune lightly in spring after the last frosts.

Want to prune your macrophylla a little more aggressively? Do so after the blooms fade in the summer before the new buds are set.

Want to reduce the size of an overgrown, wayward macrophylla while guaranteeing some blooms? Prune off 10-30% of the stems near the base to encourage new growth. Blooms will still appear on the old stems. Repeat the process over a few years.

Recommended Products

My Secateurs:

Gruntek secateurs for pruning hydrangeas

Key Points:

  • Bypass secateurs.
  • Cuts stems up to 20mm.
  • Super sharp and easy to sharpen 40mm blade.
  • Teflon coated.
  • One of the highest-rated secateurs on Amazon.
  • Ergonomic handle for comfort.

The Best Sharpening Tool:

Sharpal pen

Uses:

  • Small and compact, it easily fits into tool belts and storage slots.
  • Use on secateurs, lawnmower blades, knives and other bladed items.
  • Double-sided – one side for sharpening blunt blades, the other for fine-tuning.
  • Long-lasting – lasts up to 10,000 strokes.

Hydrangea Feed I’m Using:

Hydrangea feed

Why You Should Use Vitax:

  • Made from slow-release pellets.
  • Hydrangeas only require 2-3 applications per year.
  • Perfect NPK ratio of 8-4-12.
  • Added magnesium to produce larger blooms.
  • 1kg bags with discounts for bulk buying.
  • It won’t change the colour of the flowers.
  • Won’t burn the plants as some liquid feeds do when spilt.

More From Daniel Woodley:

This guide to pruning hydrangea macrophylla, aborescens, paniculata and oakleaf was created by Daniel Woodley here at DIY Gardening and was last updated on the 22nd of August, 2021.

Explore more hydrangea growing guides here.

Daniel is a keen amateur gardener who completely redesigned his garden and is continually experimenting with new ornamental plants and products.

He also enjoys growing vegetables and fruits in addition to his herbaceous border and container garden.

More About Daniel Woodley

Danny Woodley

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