Why Coastal Gardens Take a Harder Hit in Winter

If you garden within a mile or two of the coast, your winter is a different beast from the one inland gardeners face. It isn't simply the cold — it's the combination of wind, salt and water. A single gale off the sea can carry salt spray several miles inland, scorching evergreen leaves and drying out buds that would otherwise sail through a frost. Wind, meanwhile, does more damage than cold alone, rocking plants until roots loosen in the soil.

The good news is that a few weekends of sensible preparation in late autumn will carry most coastal plots through to spring. The trick is to work with the conditions rather than fight them: shelter what you can, drain what you must, and accept that some plants will always need replacing after a hard winter. Here's how to get your garden ready before the first real storm arrives.

Secure Structures Before the Gales Arrive

Loose fences, wobbly arches and rattling greenhouses are the first casualties of a coastal storm, and once they go, they take plants with them. Walk your plot on a calm day and give everything a firm shake.

• Fences and trellis: check posts for rot at ground level and replace any that move. Add diagonal bracing to long runs and consider open slatted designs that let wind pass through rather than solid panels that act as sails.
• Climbers and roses: retie stems to their supports with soft twine or rubber ties, loosening anything that has grown tight. Check wall shrubs for stems rubbing against fixings.
• Greenhouses and cold frames: replace missing glazing clips, oil hinges and latches, and clear leaves from gutters so rainwater can't pool and crack panes.
• Pots, obelisks and garden furniture: move lightweight items into a shed or garage, or lay tall pots on their sides so they can't be blown over.
• Young trees: check stakes and ties on anything planted in the last three years. Firm the ground around the roots with your heel, as wind rock opens gaps that let frost in.

If you have a shed or summerhouse, clear the roof of overhanging branches now — a wet, windy night is the worst time to discover that a bough is resting on the felt.

Drain Containers and Raise Your Pots

Waterlogging kills more coastal plants than cold ever does. Mediterranean favourites such as lavender, rosemary, cistus and thyme detest sitting in sodden compost, and a pot that can't drain will rot their roots long before spring.

• Remove saucers and drip trays so excess water escapes freely.
• Check the drainage holes — roots and compacted compost often block them. Stand pots on feet, bricks or gravel to lift them clear of standing water.
• Wrap terracotta and glazed pots in bubble wrap, hessian or old fleece secured with twine. This stops the freeze-thaw cycle cracking the pot and insulates the roots at the same time.
• Group pots together in a sheltered corner against a wall, ideally with their backs to the prevailing wind.
• For large permanent containers, slide a piece of slate or a tile under one side to create a slight tilt and stop rainwater collecting.

Empty any water butts or barrels that have cracked, and make sure overflow pipes direct water away from the base of walls and paths.

Mulch Bare Soil and Protect Roots

A generous mulch does two jobs on the coast: it insulates roots against frost and stops heavy winter rain from battering bare soil into a compacted pan. Aim for a layer about 5–7cm deep, using well-rotted manure, garden compost or composted bark.

Spread it across borders, around the base of shrubs and over any bare ground between perennials. Keep it clear of stems, tree trunks and the crowns of herbaceous plants, leaving a small collar of bare soil so water doesn't sit against the plant and encourage rot.

Around alpines and silver-leaved plants, a top-dressing of grit is better than compost — it keeps the foliage dry and reflects light back onto the leaves. For tender specimens such as tree ferns, cordylines and phormiums, tie the fronds up over the crown and pack the centre with dry straw or fleece. A makeshift windbreak of netting or woven willow, fixed on the seaward side of a border, will cut salt spray by a surprising amount without blocking light.

Prune Damaged Branches and Tidy Up

After a storm, resist the urge to tidy everything at once. Deal with safety first, then tidiness.

• Remove any branch that is cracked, hanging or torn. Use sharp, clean secateurs or a pruning saw and cut back to a healthy outward-facing bud or the branch collar.
• Don't paint wounds with sealant — modern advice is to leave them to callous naturally.
• Clear fallen leaves from lawns, paths and drains. A thick mat of wet leaves smothers grass and blocks gullies within days.
• Cut back collapsed perennials and stake anything that's flopping, but leave seedheads in place where they add structure and food for birds.
• Delay hard pruning of shrubs and roses until late winter or early spring, unless a branch is damaged — fresh cuts made now are vulnerable to windburn and die-back.

Check Drainage to Prevent Waterlogging

Standing water is the quiet killer of coastal gardens. Heavy clay or compacted soil holds winter rain like a basin, and roots that sit in it through December and January will rot even if the plant is perfectly hardy.

• Test suspect areas by digging a spade-deep hole and filling it with water. If it hasn't drained within a few hours, you have a problem.
• Fork over compacted borders, working in plenty of organic matter to open up the structure.
• Clear gullies, drains and soakaways of leaves and grit, and check that paths and patios fall away from the house.
• For persistently wet spots, dig a shallow drainage channel or French drain leading to a soakaway, or simply plant into a raised bed.
• Choose damp-tolerant plants for the worst corners — dogwood, willow, astilbe and Siberian iris all cope well.

Do the groundwork now, while the soil is still workable and the weather is kind, and your coastal garden will come through the gales far better placed to grow away strongly next spring.