A Garden Designer's Guide to Cornish Coast Planting

Most gardening advice pitched at “the UK coast” is too broad to be useful. The microclimates in Cornwall have specific quirks that a garden design has to actually engage with.

Prevailing wind is south-westerly and relentless. Most of the year the wind comes off the Atlantic, up over the sands, and hits any garden along the coast strip with almost no natural break. Salt spray reaches further than most people expect - on a big blow, salt-laden mist can reach a quarter of a mile inland. Winters are unusually mild: the Cornish north coast benefits from the same Gulf Stream influence as the Scilly Isles, softened. Frost is rare and rarely hard. And summer drought is real and increasing - long dry spells in June, July, and August are the new normal.

The single most important structural decision in a Cornish coastal garden is where the shelter belt goes. Once that’s in, everything else becomes possible. Good candidates: Escallonia macrantha (glossy evergreen, dense, salt-tolerant), Griselinia littoralis (the classic Cornish coastal hedge), Olearia macrodonta (silver-undersided daisy bush), Pittosporum tenuifolium in darker cultivars (‘Tom Thumb’, ‘Purpureum’) which hold in wind better than the pale green forms, or a mixed native hedge of Blackthorn, Hawthorn and Sea Buckthorn.

Because of the mild winters, a Cornish coastal garden can support plants that struggle inland: Echium pininana (the tower of blue that signals coastal Cornwall like nothing else), Agapanthus in the ground rather than in pots, Astelia chathamica (silver spear-leaved New Zealander), tender salvias like Salvia leucantha and Salvia guaranitica that overwinter reliably here.

Where in the garden matters as much as what. The west and south-west boundaries take the brunt of the weather - plant your toughest, densest material there. The east side and against north-facing walls enjoy a rain-shadow effect and much less wind exposure - that’s where the tenderer, more delicate planting goes. South-facing walls become sun traps ideal for figs, fig-relatives, and Mediterranean herbs. North-east corners stay cool and often damp - a shade garden opportunity most people don’t realise they have.

Mapping your specific garden’s microclimate before you plant anything is worth an afternoon. The garden then designs itself around what each zone actually offers, rather than fighting the site for the picture in your head.