Flowers in winter are a test of autumn preparation. The roses, bulbs, perennials and containers that survive winter well are usually the ones that were planted in the right place, mulched in autumn, and left alone at the right times — not the ones that were fussed over in January. Winter flower care is mostly about protection, patience and a few well-timed jobs: protecting tender plants, leaving the right things standing, and resisting the urge to tidy everything away. This guide explains what flowers need in winter, what to cut back, what to leave, and what to do when spring starts to stir.
The first decision is which plants are hardy in your zone and which are not. Hardy perennials, bulbs and shrubs will survive winter outdoors with a mulch and a little protection. Tender perennials, half-hardy annuals and plants from warm climates will not survive a frost, and they need to be lifted, moved under cover, or treated as annuals. If you do not know a plant's hardiness, check the label, a reliable reference, or your local extension service — guessing wrong is the most common cause of winter flower losses.
Roses in winter
Roses are the flower most gardeners worry about in winter, and in most temperate zones they need less help than people think. Do not prune roses hard in autumn or midwinter: pruning encourages soft new growth that frost damages, and it removes the wood that protects the plant. The main autumn job is to cut back very long, wind-rocked stems by about a third, so winter wind does not rock the plant and loosen its roots, and to clear fallen leaves from around the base, because rose leaves can carry black spot and other diseases into spring. Our black spot roses guide covers the disease to clear away, and the growing roses guide covers roses through the year.
In cold zones, mound mulch or compost around the base of the rose, up to 15 cm deep, to protect the graft union — the swollen joint near the base where the variety was grafted onto the rootstock — because if the graft is killed by frost, the plant may regrow as the rootstock instead of the variety you bought. In mild zones, a lighter mulch is enough. Remove the mulch gradually in spring when growth resumes. Do not feed roses in winter, and do not spray them unless a specific problem needs it. Hard pruning waits until late winter or early spring, when the buds are starting to swell and you can see what is alive.
Bulbs in winter
Bulbs are the quiet success of winter flower care: tulips, daffodils, crocuses and other spring bulbs are underground all winter, doing nothing visible, and they need almost nothing from you. The main jobs are to make sure they were planted at the right depth in autumn — too shallow and they can be heaved out by frost, too deep and they may not flower well — and to mulch over them if they were planted late or the winter is very cold. Do not dig them up in winter to check them, and do not water them: winter rain is enough, and wet soil around bulbs can cause rot. Our growing tulips guide covers the planting side, and the winter mulching guide covers the mulch that protects them.
Tender bulbs such as dahlias, gladioli and tuberous begonias are different: they must be lifted before the first hard frost in cold zones, dried, and stored in a cool, frost-free place in dry compost or peat-free material. If you left them in the ground in a mild zone, mulch them heavily and hope for a mild winter — but in zones 1 to 5, lifting is the honest advice. Check stored bulbs through winter, remove any that are soft or mouldy, and keep them dry and cool until spring.
Perennials: what to cut back and what to leave
The old advice was to cut everything back in autumn and tidy the garden for winter. The better advice is to leave most perennials standing until spring. Dead stems and seed heads protect the crown of the plant from frost, give shelter to insects and birds, and look good in frost. Plants with hollow stems, such as delphiniums, should be cut back to a few centimetres and the cut ends protected, because water can run down a hollow stem and rot the crown. Plants that are prone to rot in wet winters, such as some penstemons and salvias, are better cut back and mulched. Evergreen perennials should be left alone, apart from removing dead leaves. Our zone 5 winter gardening guide shows how perennial care changes with the zone.
In spring, cut back the dead growth before new shoots emerge, but not before the worst frosts have passed — cutting back too early exposes the crown. Compost the dead material if it is healthy, and dispose of diseased material separately. Divide overcrowded perennials in late winter or early spring, when you can see the new shoots, rather than in midwinter when the plant is dormant and the ground may be frozen.
Containers and tender plants
Flowers in pots are more vulnerable than flowers in the ground, because a pot has no earth around it to buffer the cold, and roots in a pot can freeze solid. Move tender container plants under cover before the first frost — into a greenhouse, a cold frame, a porch or a bright indoor spot. Hardy container plants can stay outside, but group pots together against a sheltered wall, raise them off the ground on pot feet so water drains away, and wrap the pots in bubble wrap, hessian or fleece to insulate the roots. Mulch the surface of the pot, and water sparingly: containers need far less water in winter, and wet compost in a cold pot can rot roots. Our winter frost protection guide covers covers and cold frames, and the winter houseplant care guide covers the plants that come indoors for winter.
Check containers after frosts: if a pot has cracked, it may be because water in the compost froze and expanded, which is why drainage and pot feet matter. Terracotta pots are more vulnerable to frost damage than plastic or glazed pots, so move valuable terracotta under cover if you can. Do not feed container flowers in winter, and do not repot them unless they are in trouble — repotting is a spring job.
Winter-flowering flowers
Not all flowers sleep in winter. Winter-flowering plants such as snowdrops, winter aconites, hellebores, winter jasmine and some witch hazels flower in the coldest months, and they need little care: just a mulch, no feeding, and no cutting back while they are flowering. Do not move them while they are in flower, and do not cut them back until flowering is over. If you have no winter flowers, note the gap now and plan to plant some in autumn — a garden with nothing in flower from November to February feels longer than it is, and a few snowdrops and hellebores make a real difference.
Common mistakes
The most common mistake is pruning roses and shrubs hard in autumn, which encourages soft growth that frost kills. The second is cutting all perennials back in autumn, which removes the frost protection their dead stems provide. The third is leaving tender bulbs in the ground in a cold zone and expecting them to survive. The fourth is forgetting containers, which freeze harder than beds. The fifth is overwatering containers in winter, which rots roots. The sixth is feeding flowers in winter, which they cannot use. And the seventh is clearing fallen rose leaves and diseased material too late, so disease carries into spring. If you are unsure about a plant's hardiness or winter care in your area, check your local extension service for advice.
Frequently asked questions
Should I cut back perennials in winter?
Usually not. Leave most perennials standing until spring: the dead stems protect the crown from frost and shelter wildlife. Cut back plants with hollow stems, and plants prone to rot in wet winters, and clear diseased material. Cut back the rest in spring before new growth emerges.
How do I protect roses in winter?
Cut back very long stems by a third in autumn, clear fallen leaves, and mound mulch around the base in cold zones to protect the graft union. Do not prune hard or feed in winter — hard pruning waits until late winter or early spring.
Do bulbs need watering in winter?
No. Winter rain is enough, and extra water can rot bulbs. Make sure they were planted at the right depth in autumn, mulch over late-planted bulbs, and leave them alone until spring.
Can container flowers stay outside in winter?
Hardy ones can, if you group pots against a sheltered wall, raise them on pot feet, wrap the pots to insulate the roots, and water sparingly. Tender container plants must come under cover before the first frost.
What flowers bloom in winter?
Snowdrops, winter aconites, hellebores, winter jasmine and some witch hazels flower in the coldest months. They need little care — just mulch and patience — and they are worth planting in autumn if your garden has a winter gap.