When to Prune a Magnolia Tree

In short: The best time to prune a deciduous magnolia in the UK is from midsummer to early autumn, roughly July to September, when the tree is in full leaf. Avoid pruning in late winter or early spring, when cuts bleed sap. Evergreen magnolias are pruned in spring as growth begins. Most magnolias need very little pruning, so only cut when there is a clear need.

At a glance

• Deciduous magnolias: prune from midsummer to early autumn, roughly July to September.
• When to avoid: late winter and spring, when cuts bleed sap and you lose that year’s flowers.
• Evergreen magnolias: prune free-standing trees in spring and wall-trained plants in summer.
• How much to cut: as little as possible, always cutting back to a natural fork or side branch.
• Overgrown magnolias: spread any renovation over two or three years.
• Protected trees: a magnolia with a Tree Preservation Order or in a conservation area needs council consent or notice first.

When is the best time to prune a magnolia tree?

The best time to prune a deciduous magnolia, such as the saucer magnolia or star magnolia, is from midsummer to early autumn. The Royal Horticultural Society (RHS) advises pruning deciduous magnolias only during this period, because cuts made in late winter or early spring are liable to bleed sap.

In practice, for magnolias in gardens across Essex that means:

• July to September: the ideal window. The tree is in full leaf, so you can see its shape clearly, and cuts start to seal before winter.
• October to December: best avoided for anything more than removing dead or damaged wood.
• January to April: avoid pruning. Sap starts rising and fresh cuts can bleed.
• May and June: wait until flowering has finished and the new leaves are fully open.

Why shouldn’t you prune a magnolia in spring?

You should not prune a deciduous magnolia in late winter or spring because the sap is rising and cuts can bleed heavily. Pruning at that time also removes the flower buds that are about to open, so you lose that year’s blooms.

Magnolias are also slow to recover from heavy pruning. Large cuts can lead to dieback and a mass of fast, upright shoots known as watershoots, which spoil the tree’s natural shape. Hard pruning can also reduce flowering.

Does a magnolia tree need pruning?

Most magnolias rarely need pruning. They grow naturally into a graceful, open shape, and the less they are cut, the better they usually flower. Pruning is best kept to a few specific jobs:

• removing dead, damaged or diseased branches
• taking out crossing or rubbing branches
• removing watershoots and suckers
• lifting low branches that block a path, drive or window

If a magnolia is healthy and has space to grow, it is often best left alone. As with every tree the Crown Tree Services team works on, the aim is to keep it healthy and flowering well, not to cut it for the sake of it.

How do you prune a magnolia tree?

To prune a magnolia, make small, clean cuts back to a natural fork or side branch, and never leave stubs. Remove as little live wood as possible. Smaller cuts heal faster and are less likely to trigger dieback or watershoots.

1. Check the timing. Prune deciduous magnolias from midsummer to early autumn only.
2. Start with dead and damaged wood. Cut back to healthy wood or to the branch it grows from.
3. Remove crossing branches. Take out any branches that rub or crowd the centre of the tree.
4. Thin lightly. Remove a few branches to open up the crown, rather than shortening lots of stems.
5. Cut to a fork. Always cut just above a natural fork or side branch, never part way along a branch.

Use clean, sharp secateurs, loppers or a pruning saw. Anything above head height or close to a building is best left to a professional team. Need help with maintenance of your magnolia tree? Get in touch with the Crown Tree Services team for a free, no obligation quote.

Can you cut back an overgrown magnolia?

You can cut back an overgrown magnolia, but it is safest to spread the work over two or three years. The RHS recommends staging renovation to avoid stressing the tree, as magnolias can be slow to recover and may produce lots of watershoots after heavy cuts.

Each summer, remove a few of the largest or most badly placed branches, then remove any watershoots that appear. For a large magnolia close to a house or boundary, careful crown thinning or a light tree crown reduction by a professional arborist like the Crown Tree Services team keeps the tree’s natural shape while making it a better fit for the space.

When should you prune an evergreen magnolia?

Evergreen magnolias, such as Magnolia grandiflora, need little pruning. Prune free-standing evergreen magnolias in spring as new growth begins. Wall-trained evergreen magnolias are pruned in summer, cutting back long shoots to keep them neat against the wall.

Do you need permission to prune a magnolia?

You may need permission to prune a magnolia if it is protected. A magnolia covered by a Tree Preservation Order (TPO) needs written council consent before pruning, and a magnolia in a conservation area needs six weeks’ written notice to the council. The Crown Tree Services team checks the status of every tree with your local authority before work begins.

Need help pruning a magnolia in Essex?

If your magnolia has outgrown its space or needs a careful prune, our team can help. Crown Tree Services offers commercial and domestic tree care and shrub pruning in Essex, always timed to protect the health and flowering of your trees. Our qualified, fully insured arborists are based in Ongar and work to British Standard BS3998:2010.

We regularly care for magnolias in gardens across the county, providing our customers with tree surgeons in Romford, tree surgeons in Hornchurch, tree surgeons in Chigwell and tree surgeons in Billericay.

Contact us online or call us on 01277 525150 to book a free site visit and fixed, no-obligation quote for your magnolia pruning.