What to cut back in autumn, and what to leave until spring

By Sophie Sparkes · October 2026 · 7 min read

The autumn tidy is a habit many of us inherited: cut everything to the ground and leave the borders bare and neat for winter. Gardeners now do much less of it, and for good reasons. Some plants genuinely benefit from being cut back in autumn, but plenty are better left standing until late winter or spring, for their own protection and for wildlife.

Short answer: cut back perennials that collapse into slimy mush or carry disease, such as peonies, hostas, daylilies and any phlox or asters with mildew. Leave anything with seedheads or structure (ornamental grasses, sedum, echinacea, rudbeckia), anything a little tender (penstemon, shrubby salvias, hardy fuchsias), and hydrangeas, whose old flowerheads protect next year's buds. Give lavender only a light trim after flowering, never into bare wood. Shorten tall roses by about a third to stop wind rock, and save the main rose prune for late winter.

Quick guide: cut back or leave?

Why leaving plants standing is often better

• Frost protection. Old stems and leaves insulate the crown of the plant, which matters for anything borderline hardy.
• Wildlife. Hollow stems shelter overwintering ladybirds and solitary bees. Seedheads feed finches, and leaf litter feeds the beetles and worms that hedgehogs and birds eat. Our guide to helping hedgehogs explains why an untidy corner matters.
• Winter interest. Grasses and seedheads catch frost and low sun when there is little else to look at.
• Knowing where things are. Old stems mark where perennials are, so you do not dig into them by accident.

When cutting back in autumn is the right call

• Disease. Leaves with mildew, rust, black spot or grey mould carry spores through the winter. Remove and bin them.
• Slugs. Soft, collapsing foliage such as hosta leaves is ideal slug shelter right next to next year's new shoots.
• Collapse. Plants that turn to slime after frost, such as hostas and some daylilies, are not providing shelter or structure, so there is no reason to keep them.
• Self-seeders. If a plant seeds itself too freely, cut the seedheads off before they drop.

Lavender: the one people get wrong

Lavender is the plant most often killed by an autumn haircut. It does not regrow well from old, bare wood, and a hard cut in autumn leaves it exposed to winter wet and cold. Instead, trim it straight after flowering in late summer: remove the flower stalks and about 2-3cm of the leafy growth, keeping the plant a rounded shape and always leaving some green above the woody base. If your lavender has already gone leggy and woody, it is usually better to replace it than to cut it hard.

Roses: why a light trim now

Long rose stems catch the wind in winter storms and rock the plant, loosening its roots and leaving a hollow at the base where water collects. In late autumn, shorten bush and shrub roses by about a third and remove any dead or diseased stems. Leave the proper prune until late winter, February or March, when you can see the buds. Clear up fallen leaves with black spot rather than leaving them under the plant.

Cutting back questions

Should I cut back perennials in autumn or spring?

Mostly spring, or late winter. Cut back in autumn only if the plant has collapsed, is diseased, or is a slug magnet like hostas. Leave plants with seedheads, structure or slightly tender crowns standing until February or March.

When should I cut back lavender in the UK?

Straight after flowering, in late summer. Remove the flower stalks and a little leafy growth, but never cut into the old, bare wood. Avoid hard pruning lavender in autumn or winter.

Should I cut back hydrangeas in autumn?

No, not mophead or lacecap hydrangeas. Leave the dead flowerheads on over winter to protect the buds, then cut back to the first pair of healthy buds in March. Panicle hydrangeas and 'Annabelle' are pruned in late winter or early spring.

When do you cut back peonies?

In autumn, once the foliage has turned yellow or brown, usually October or November. Cut the stems to ground level and bin the leaves if they had grey mould. Tree peonies are shrubs and should not be cut down.

Should I cut back hostas in the autumn?

Yes. Once frost collapses the leaves, remove them. Left in place, they rot down and give slugs and snails a sheltered home right where the new shoots will appear in spring.

Should I cut back crocosmia leaves?

Not in autumn. The old leaves help insulate the corms over winter, especially in colder parts of the UK. Remove them in late winter or early spring, before new growth comes through.

When should I cut back ornamental grasses?

Deciduous grasses such as miscanthus and pennisetum are cut to near the ground in February or March, before new growth starts. Evergreen grasses are not cut back hard: just comb out the dead leaves in spring.