Best Outdoor Plants for British Coastal Gardens

The best plants for coastal gardens are not simply those that can handle a chilly winter. They need to withstand salt-laden winds, exposed conditions and the free-draining soils that come with life by the sea. Fortunately, coastal gardening comes with its own hidden advantage: the surrounding sea can create a milder, frost-buffered microclimate, opening the door to a surprisingly exotic range of plants.

Below, we’ve rounded up ten of the best plants for seaside gardens, all grown and dispatched by us, with their RHS hardiness rating, mature size and an honest guide to how much shelter each one needs to flourish.

Why do coastal gardens suit exotic planting?

The sea works as a giant heat store. Coastal air stays warmer through winter nights, frosts arrive later and lift earlier, and that is why the RHS observes that exotics such as bottlebrush, Cordyline and daisy bush often struggle inland yet thrive in seaside gardens. Cornwall, Pembrokeshire, the Gower, Argyll and the milder stretches of the east coast frequently sit a full hardiness band above comparable inland plots.

However, salt spray scorches soft new growth, constant wind pulls moisture from leaves faster than roots can replace it, and sandy soil drains so freely that nutrients wash straight through. Choose for those three conditions and coastal gardening becomes easier than inland gardening, not harder. 

What to plant in a coastal garden

The secret to successful coastal planting is to think in three layers, and in this order. Skipping the first is one of the most common reasons coastal gardens struggle.

• Shelter first. Nothing planted behind it can perform at its best if it is taking the full force of the wind. A permeable screen that filters and slows the wind is far more effective than a solid wall, which can create damaging turbulence on its leeward side.
• Structure second. Build the backbone of the garden with evergreen shrubs, fan palms and spiky architectural plants that can cope with exposed conditions while keeping the garden looking good through winter. These are the plants that bring height, form and a distinctly exotic feel, without needing to be mollycoddled.
• Detail last. Once your shelter and structural planting are in place, fill the front of the garden with grasses, restios and tough evergreen perennials. These add movement, texture and seasonal interest while benefiting from the calmer conditions created by the layers behind them.

Best plants for coastal gardens

Griselinia littoralis

The definitive UK coastal hedge and an RHS top-five pick for seaside planting. Griselinia littoralis, or kapuka, carries glossy apple-green evergreen leaves on a bushy frame. Left unclipped it reaches 4 to 8m over 10 to 20 years, but it takes a shear happily and holds any height from about 1.5m upwards. RHS hardiness H5, rated for exposed positions, and it accepts chalk, clay, loam or sand. Nothing else here combines salt tolerance and hedging discipline so neatly.

Olearia traversii

The Chatham Island daisy bush is what coastal nurseries reach for when a site is genuinely brutal. Olearia traversii is evergreen, felted silver beneath, RHS H4 and rated exposed. Left alone it makes 8 to 12m, so treat it as a clipped shelter belt or hedge rather than a free-standing specimen unless you have real space. Full sun, well-drained soil, no fussing.

Chamaerops humilis

Salt does not trouble the European fan palm, which is why it turns up in seafront planting from Torquay to Tenby. Chamaerops humilis holds an RHS Award of Garden Merit, sits at H4, stays compact at 1.5 to 2.5m tall by 1 to 1.5m across, and is rated for exposed positions. It is slow, taking 20 to 50 years to reach ultimate height, which makes it an excellent permanent container plant. More options in our guide to the best hardy palms.

Yucca gloriosa

For unapologetic architecture, Yucca gloriosa gives a columnar 2 to 3m of rigid blue-green blades topped by cream flower spikes from August to October, and it is a genuine pollinator plant. RHS H5, full sun, exposed, sharp drainage. The leaf tips are properly spiny, so site it well clear of paths and play areas.

Elegia tectorum

Cape thatching reed looks like a bamboo crossed with a horsetail and is one of the most underused coastal plants in Britain. Elegia tectorum forms a 1 to 1.5m evergreen clump, RHS H4, rated exposed, and reaches full size in 2 to 5 years. Sandy or loamy soil that stays moist but well-drained suits it precisely.

Eryngium agavifolium

If you like the sea holly look but want it evergreen and permanent, the agave-leaved sea holly is the upgrade. Eryngium agavifolium sends 1 to 1.5m branched stems over a rosette of saw-toothed leaves, flowering July to September. RHS H4, full sun, exposed, and it demands free drainage.

Kniphofia rooperi

Red hot pokers are a seaside staple and this is the best of the late ones. Kniphofia rooperi flowers September into October at 1.2 to 1.5m, stays evergreen, and is RHS H5. It works in full sun or partial shade and is rated for exposed sites.

Miscanthus sinensis 'Strictus'

Porcupine grass is the movement-and-screening workhorse. Miscanthus sinensis 'Strictus' stands stiffly upright at 1.8 to 2.5m on a tight 0.5 to 0.6m footprint, so it screens without sprawling, and at RHS H6 it is the hardiest plant on this list. It is deciduous, so cut it back in late winter. Browse the wider range in ornamental grasses.

Libertia peregrinans

New Zealand iris is the front-of-border answer for a windy plot. Libertia peregrinans spreads as an evergreen groundcover at 0.5 to 1m tall, with orange-bronze blades that intensify in low winter sun. RHS H4, rated exposed, and content on chalk, loam or sand.

Fargesia rufa

For a fast, permeable windbreak, clumping bamboo is hard to beat. Fargesia rufa reaches 2 to 3m with a 1.5 to 2m clumping, non-running footprint, is RHS H5 and rated exposed, and it filters wind rather than blocking it. See the full options in screening plants, or read our guide to evergreen screening plants under 3m.

At a glance:

What plants do well in salty soil and salty air?

Salt tolerance sits on a spectrum, and the useful distinction is front rank against second rank. Front-rank plants take direct salt spray off the water: Griselinia, Olearia, Yucca, Libertia and the restios all belong here, which is why every one of them carries an exposed rating on its own product page.

Second-rank plants want the same mild coastal air but need something between them and the spray. Three worth planting once you have shelter: Leptospermum scoparium, the New Zealand tea tree, at RHS H4 and 1.5 to 2.5m but listed sheltered; Fascicularia bicolor, a hardy bromeliad at H3 that turns its centre crimson before flowering and is a Cornish garden classic; and Myosotidium hortensia, the Chatham Island forget-me-not, at H3 and happiest in partial shade with reliable moisture. Site those three behind the hedge, not in front of it.

On soil itself, sand is the usual coastal reality. It drains fast, holds few nutrients and warms early. Improve it with generous organic matter at planting and expect to feed more often than an inland gardener would, rather than trying to change the soil type outright.

Small coastal gardens and coastal pots

A small seaside plot does not need a shelter belt, it needs one well-placed windbreak and tougher plant choices. A single Fargesia clump or a clipped Griselinia panel on the prevailing-wind side transforms what you can grow behind it, and both suit a large container.

For pots specifically, choose slow and salt-proof over fast and thirsty. Chamaerops humilis is the obvious anchor. Stipa tenuissima 'Ponytails' gives 45 to 60cm of constant movement at H4 with an exposed rating and looks its best in wind rather than despite it. Add Libertia for winter colour at the pot edge. More ideas in plants for pots.

Shop the coastal range at GrowTropicals

Every plant mentioned above is in our coastal and exposed plants collection, with hardiness band, mature size, aspect and exposure listed on each product page so you can match a plant to your site before you buy. If you want the wider picture, the hardy exotics range covers everything that survives a British winter outdoors, and plants for full sun overlap heavily with the coastal list. All plants are shipped directly from our nursery to your door.