section heading hidden

Why Coastal Gardens Need a Different Approach

If you garden within a few hundred metres of the sea, you already know that the forecast on your plot rarely matches the one on the radio. Even on a still day, a stiff onshore breeze can carry a fine mist of salt several miles inland, and that salt settles on leaves, buds and soil. It draws moisture out of plant tissue, scorching foliage and stunting growth, while the wind that carries it dries everything out far faster than you would expect inland.

The soil presents its own challenges. Seaside plots are often thin, sandy and free-draining, sometimes alkaline where shell fragments have built up over the years, and rarely rich in the organic matter that holds water and nutrients. The good news is that once you understand these conditions, you can work with them rather than fighting them. Coastal gardening is less about cosseting and more about choosing the right plants, then giving their roots a fighting chance.

Plants That Shrug Off Salt Spray

Look closely at plants that flourish naturally on the coast and you will notice a pattern: small or leathery leaves, waxy or felted surfaces, silver-grey foliage, and a preference for sharp drainage. Choose in that mould and you will spend far less time nursing casualties.

• Sea thrift (Armeria maritima) forms tight pink-flowered cushions that cope with salt, wind and poor soil in equal measure. Ideal at the front of a border or in gravel.
• Sea holly (Eryngium) brings architectural blue-grey foliage and thistle-like flower heads, and resents nothing except wet winter roots.
• Mediterranean herbs — lavender, rosemary, thyme, sage and Santolina — thrive in the dry, lean conditions coastal plots provide. Their aromatic oils help them cope with wind and salt.
• Rock roses (Cistus) are short-lived but dazzling, flowering generously through summer on the hottest, most exposed banks.
• Hebe, escallonia and Griselinia littoralis form dense, wind-firm evergreens that double as shelter for more tender plants.
• Hardy geraniums, sedums, crocosmia, blue fescue and hydrangeas all earn their place, as do the tough rugosa roses.

Edible growers need not miss out. Kale, chard, beetroot, chives and rosemary all cope well in a raised bed, especially one sheltered by a low hedge. Avoid delphiniums, lupins, and anything with soft, large leaves unless you can offer real protection.

Create Shelter Before You Plant

The single most effective thing you can do for an exposed plot is to slow the wind down before it reaches your borders. A solid wall or fence seems like the obvious answer, but it creates damaging turbulence on the leeward side and actually increases the force of gusts. What you want is a permeable barrier of roughly 50 per cent porosity, which filters the wind rather than blocking it.

Woven hurdles, slatted fencing, windbreak netting or a well-sited hedge all do the job. Planted hedges are the best long-term investment, and tough evergreens such as escallonia or griselinia will knit into an effective screen within three or four years. Plant two staggered rows rather than a single line, and keep the hedge trimmed so it does not become too dense at the base, which is where gaps let the wind through anyway.

Position your barrier around three to five times its eventual height away from the plants you are protecting. If you are starting from scratch, put the shelter in first and give it a couple of seasons before you plant anything precious behind it.

Look After the Soil and the Roots Beneath It

Roots are where the real battle is won or lost. Salt accumulates in the soil, wind erodes the surface, and sandy ground leaches nutrients quickly, so building soil structure matters more than feeding.

• Mulch generously every spring with well-rotted compost or leaf mould, 5–8cm deep, keeping it clear of stems. This conserves moisture, suppresses weeds and slowly improves sandy soil.
• Rinse off salt crusts. After a spell of strong onshore winds, a good soak with the hose washes salt through the root zone rather than letting it concentrate there.
• Water deeply but less often. Shallow daily sprinkling encourages weak surface rooting. A thorough soak once or twice a week does far more good.
• Use a grit mulch around Mediterranean plants and alpines. It stops wind lifting the soil surface and keeps the collar of the plant dry.
• Plant in autumn where you can, so roots establish through the mild, damp months before the winds return. Remember to stake or shelter new arrivals with a temporary netting cage or windbreak for their first season.
• Go easy on nitrogen-rich feeds late in the season, as soft sappy growth is the first thing salt and wind will damage.

A Year of Coastal Care

Spring: top up mulches, repair any winter damage to fences or netting, and feed established plants lightly as growth restarts. This is the moment to replace anything lost over winter.

Summer: deadhead to keep flowers coming, water deeply during dry spells, and rinse foliage after particularly salty winds. Keep an eye on containers, which dry out alarmingly fast in coastal sunshine.

Autumn: the ideal planting window. Get new shrubs and perennials in while the soil is still warm, and firm everything in well so roots are not rocked loose by winter gales.

Winter: check stakes and ties before the worst of the weather, wrap or move tender pots against a sheltered wall, and leave spent seed heads and stems standing as shelter for wildlife and as a natural wind filter.

Coastal gardening asks for a little patience at the start and rather less effort later on. Build your shelter, improve your soil, and choose plants that evolved for exactly these conditions, and you will end up with a garden that looks good whatever the sea throws at it.