Why the Coast Is a Different Kind of Garden

If you garden within a few miles of the sea, you already know that conditions are rarely gentle. Salt spray carried on the wind settles on leaves and buds, drawing moisture out of the tissue and scorching foliage that would look perfectly healthy inland. Add persistent onshore winds, which can bend and bruise growth, and a growing season that shifts a fortnight either way depending on the year, and you have a site that demands a different approach. The good news is that once you work with the coast rather than against it, seaside gardens can be rewarding, distinctive places full of character.

The three factors that matter most are salt, wind and drainage. Sort those and the range of plants available to you widens considerably.

Plants That Shrug Off Salt Spray

Start by choosing species that evolved on coastlines elsewhere. Grey, glaucous and waxy leaves are a strong clue that a plant copes with salt, because the surface layer resists moisture loss. Fleshy leaves, as seen on sedums and sea thrift, hold their own water. Hairy or needle-like foliage helps too.

Reliable shrubs for exposed coastal plots include Griselinia littoralis, Escallonia, Pittosporum tenuifolium, Elaeagnus, Olearia and Tamarix, which is happy even in ground that occasionally feels a sea breeze's full force. Rosa rugosa, the salt-spray or rugosa rose, is almost bulletproof and gives you scent and hips into autumn.

For perennials and ground cover, try sea thrift (Armeria maritima), sea holly (Eryngium), Lavandula, Cistus, Sedum, Crocosmia, Verbena and Glaucium flavum, the yellow horned poppy, which seeds itself about happily on shingle. Grasses such as Stipa and Festuca add movement without asking for much.

• Avoid planting tender, soft-stemmed plants on the windward boundary.
• Plant in autumn where you can, so roots settle before the gales arrive.
• Group plants closely to reduce wind tunnelling between them.
• Keep new plantings watered with fresh water during their first summer.

Building a Shelter Belt That Actually Works

A solid wall or fence seems like the obvious answer, but it usually makes things worse. Wind hits it and swirls over and around, then drops down as damaging turbulence on the other side. What you want is a porous barrier that filters wind and slows it to roughly half its speed across a distance of about ten times its height. Hedge, mesh or hurdle are all better choices than solid timber.

Plant a shelter belt on the windward side of the garden, ideally two or three staggered rows deep. Space plants so the hedge is roughly 50 per cent permeable once established, which allows some air through rather than blocking it entirely. Good components include Griselinia, Escallonia, Tamarix, Elaeagnus and the tough native Sambucus nigra. If you need cover immediately, use windbreak netting or willow hurdles fixed to posts while your hedge grows.

Prune the windward face of a coastal hedge lightly and regularly rather than hard. Shearing it into a tight box only encourages dense, brittle regrowth that tears in a storm. Trim in spring, not autumn, so any soft cut surfaces have the whole growing season to harden before winter.

Getting Water and Drainage Right

Coastal soils often come in two frustrating flavours. Sandy, free-draining ground lets water pour through, so nutrients and moisture vanish just when plants need them. Heavy clay or compacted subsoil sits wet in winter and bakes hard in summer.

For sandy ground, dig in plenty of well-rotted organic matter and mulch generously every spring. A layer of compost, leaf mould or seaweed-based soil conditioner holds moisture and slowly feeds the soil. Raised beds lift plants above a wet water table and warm up faster in spring, which matters on cold, wind-battered sites.

For clay, add grit and organic matter together, and consider planting on a slight mound so crowns never sit in standing water. Terracing a sloping plot slows runoff and gives you pockets of deeper soil. Whatever your soil type, avoid overwatering after plants are established — most coastal plants are far more tolerant of drought than they are of soggy roots.

• Mulch annually to lock in moisture and suppress weeds.
• Plant on a slight mound in heavy soil to keep crowns dry.
• Add grit to clay, compost to sand — improve both together.
• Use raised beds on very exposed or waterlogged plots.

Protecting and Maintaining Through the Year

After a strong onshore gale, a quick rinse with fresh water from a watering can or hose washes salt off foliage and gives plants a chance to recover. This is worth doing after any notable storm, especially on evergreens and anything newly planted.

Mulching does double duty on the coast: it keeps roots cool and moist, and it stops salt-laden soil splashing up onto leaves during heavy rain and wind. A generous spring mulch of compost or bark will pay for itself many times over.

Give young plants a little extra shelter for their first two winters using windbreak netting or a temporary screen of brushwood. Once roots are deep and wood is ripened, most will fend for themselves. Avoid high-nitrogen feeding late in the season, because it pushes soft growth that the first gale will shred.

Containers, Slopes and Small Coastal Spaces

Not every coastal plot has room for a full shelter belt. If you are working with a balcony, a courtyard or a narrow strip of shingle, containers work well as long as you choose them carefully. Use large, light-coloured pots, which reflect heat and dry out more slowly than small dark ones, and fill them with a gritty, free-draining compost. Sea thrift, lavender, sedums, rosemary and festuca grasses live happily this way for years.

On steep or terraced ground, plant low, spreading species along the top of each bank so roots bind the soil and wind passes over rather than through. Silver and grey foliage reflects the light beautifully and tends to be the toughest option you have. With a thoughtful shelter belt, the right plant choices and soil that drains freely, a coastal garden becomes not a battle against the sea but one of the most atmospheric places you could hope to grow anything.