Plants and Planting · 24 October 2026 · 5 min read

Overwintering Pots and Containers: Protecting Plants from Frost and Wet

Container plants have a harder time in winter than those in the ground. Roots in a pot are exposed to cold from all sides, and a pot can become waterlogged in a way that open ground rarely does. A little preparation in late October, before the first hard frosts, makes the difference between plants that come through and a pot of mush in March.

In much of northern England, the first frosts typically arrive between late October and November, though it varies year to year and place to place. Coastal areas are often milder but more exposed to wind and salt.

Wet is often worse than cold

Many plants that are fully frost hardy in the ground die in pots because the compost stays soaked all winter. So the first rule of overwintering pots is: get the drainage right.

• Raise pots off the ground on pot feet, bricks or slates so water can drain freely and not freeze against the base.
• Check drainage holes are clear and not blocked with debris.
• Move pots out of the rain where possible, for instance against a house wall under an overhang, particularly plants that dislike winter wet, such as lavender, rosemary and many alpines and Mediterranean plants.
• Tilt pots slightly on their sides in a sheltered spot if rainfall is a risk, for very wet-sensitive plants, taking care that they do not dry out completely.

Protect the pot itself

Not all pots handle freezing. Cheap terracotta can absorb water, which expands on freezing and cracks or flakes the surface. Look for pots labelled as frost-resistant, or move vulnerable pots into a sheltered, frost-free place like a shed, porch or unheated greenhouse. Plastic, fibreglass, wooden and well-fired glazed ceramic containers usually cope better.

To insulate pots in the open:

• Wrap the pot in bubble wrap, hessian, or horticultural fleece, tied or taped in place. Leave the top open for drainage, unless the plant itself needs protection.
• Group pots together in a sheltered spot, such as against a south- or west-facing wall. The pots protect each other, and the house wall gives a little warmth.
• Mulch the top of the compost with bark chips or straw to protect surface roots.

Which plants to bring in, which to leave out

Hardy plants such as most evergreen shrubs, heathers, hardy ferns, hostas, many herbs like thyme and sage and spring bulbs generally cope in pots outdoors if the drainage is good and they are moved to shelter in extreme weather. Planted bulbs in pots are covered in our bulb guide.

Half-hardy and tender plants need protection from frost or must come inside before the first frost. These include:

• Pelargoniums (geraniums): Lift, shake off most of the soil and pot up in dry compost, or keep in a frost-free, bright place with minimal water. Cut back a little.
• Fuchsias (tender types): Keep the pots in a frost-free shed or greenhouse, keeping the compost only barely moist. Hardy fuchsias can stay out if well mulched.
• Dahlias: In colder regions, many gardeners lift the tubers after the first frost blackens the foliage, dry them off and store them in a frost-free place in slightly damp compost or paper. In milder areas with free-draining soil they may survive under a thick mulch, but in pots the risk is higher, especially in the north.
• Cannas, begonias and other tender perennials and tubers: Treat similarly to dahlias.
• Citrus, olive, agapanthus and tender shrubs: Move into a bright, cool, frost-free place. Check hardiness for the particular plant.

Check each plant's hardiness rating (for example the RHS H1 to H7 scale) and be cautious, since a plant listed as borderline might survive a mild winter and then die in a hard one.

Watering in winter

Plants use less water in winter, and overwatering is the commonest cause of loss.

• Outdoors: Rain is often enough. Check pots under cover or in the lee of a wall regularly, because they can dry out completely.
• Indoors or in a greenhouse: Water sparingly, only when the compost is nearly dry, and in the morning so that foliage dries before nightfall.
• Never leave pots standing in saucers of water in cold weather.
• Do not feed during winter. Feeding encourages soft growth, which frost damages.

Pests and diseases

Before bringing plants indoors or under cover, check for slugs, snails, vine weevil grubs, aphids and diseases. Remove dead leaves, which can harbour grey mould (botrytis). Ventilate a greenhouse on mild days to prevent mould, as the damp air does more harm than the cold in a closed space.

Using fleece

Horticultural fleece is a light cover that gives a few degrees of protection. Wrap shrubs, or drape it over a frame so it does not touch the foliage. Remove it on mild days so the plant gets air, and make sure it is secured against the wind. In a severe frost, double up the layers. Fleece protects against frost, not against wet, so the drainage still matters.

Wind

On exposed sites, the wind can topple pots and desiccate evergreens. Move tall or top-heavy containers against a wall or fence, or lay them down, and use heavier pots where possible. Check that fences are secure; see our post on choosing a fence and setting posts for tips on resilience.

After a hard frost

Do not rush to prune frost-damaged growth. It protects the lower parts of the plant, and cutting it back too early can expose new shoots to later frosts. Wait until spring, when you can see where new growth begins. If a pot has frozen solid, do not move it until it thaws, because the roots can be damaged.

Your late October checklist

1. Check the forecast and be ready to protect plants on frosty nights.
2. Lift pots onto feet, and clear drains.
3. Move tender plants under cover or lift tubers.
4. Wrap vulnerable pots and group them in a sheltered spot.
5. Cut back on watering and stop feeding.
6. Clean up dead leaves and check for pests.

Plenty of what you need can be done in a single afternoon, and it is worth doing before the weather turns. It is also a good moment to tidy the leaves from the patio, as covered in clearing leaves, and to give a thought to the compost heap, which we covered here.