Planting a Windbreak of Native Trees

Why the Coast Needs a Windbreak First

If you garden within a few miles of the sea, you already know the wind is the real head gardener. It strips moisture from leaves faster than the roots can replace it, scours tender growth with salt spray, and snaps anything with ambitions above knee height. A fence or wall seems the obvious answer, but solid barriers actually make things worse: the wind hits them, eddies over the top, and dumps a churning downdraught on whatever you planted for shelter.

What you want is a shelterbelt — a semi-permeable barrier that filters the wind rather than blocking it. A porous band of trees and shrubs slows airflow, letting perhaps half of it through. The result is a calmer, warmer, less salty pocket of garden, often extending to about ten times the height of the hedge downwind. A modest 2 metre native hedge can therefore shelter a good 20 metres of border. That is a genuine microclimate, and it is the single best investment you can make on an exposed plot.

The Case for Native Trees

Native species have spent millennia adapting to British conditions, and the toughest of them cope admirably with maritime exposure. They also support far more wildlife than most exotic alternatives: haws and sloes feed winter thrushes, rowan berries are a magnet for redwings and fieldfares, and the thorny tangle provides nesting cover that cats find genuinely difficult to penetrate.

Three species do the heavy lifting in a coastal shelterbelt:

• Hawthorn (Crataegus monogyna) — the backbone of any coastal hedge. Fiercely hardy, tolerant of salt-laden wind, happy on chalk, clay or sand, and it clips beautifully once established.
• Blackthorn (Prunus spinosa) — slower and more sprawling, but exceptionally wind-fast, with dense suckering growth that knits a hedge together. White blossom in earliest spring, sloes in autumn.
• Rowan (Sorbus aucuparia) — a small tree rather than a hedging shrub, ideal for the middle or inland-facing row where it gets a little protection. Handsome pinnate leaves, scarlet berries and excellent autumn colour.

If you want to add variety, field maple, wild cherry and sea buckthorn all earn their place, but the three above will get you a functional windbreak on almost any coastal soil.

Planning the Shelterbelt

Orientation matters more than anything else. Identify your prevailing wind — for most of the UK coast that is south-westerly, but check your own site, because local cliffs focus wind in surprising directions. Plant your belt perpendicular to that wind, running across the garden rather than along it.

Two staggered rows are far better than one. Space plants about 1.5 metres apart within the row, with the second row offset by half that distance and set 2 to 3 metres behind the first. Put the hardiest material — hawthorn, blackthorn — in the windward row, and the more delicate rowan behind it. Leave at least 3 metres between the hedge and your boundary, and the same on the garden side, so you can reach it with shears and so roots do not compete with your borders.

Do not be tempted to plant right up against a sea wall or the very front of the plot. A little breathing room lets the belt develop a natural windward profile, which sheds wind far more effectively than a flat-topped line.

Planting and Establishment

Bare-root stock, lifted and replanted between November and March, is cheaper and establishes faster than container-grown plants. Order native hedging whips of 60–90cm — bigger is not better; small whips settle in quicker.

• Clear a strip at least 1 metre wide of grass and perennial weeds. Competition in the first two years is the main reason shelterbelts fail.
• Improve the soil along the row with well-rotted compost or seaweed-based organic matter, particularly on thin sandy or shingly ground.
• Plant to the same depth the whips were growing before, firm in well, and water thoroughly even if rain is forecast.
• Fit a spiral guard against rabbits and voles, and stake only where the ground is very loose.
• Mulch with a generous 7–8cm of bark or compost, keeping it clear of the stems.

Water deeply through the first two summers, and keep the strip hoed or mulched. After that, the hedge should look after itself.

Aftercare, Trimming and Wildlife

Let the hedge grow freely for the first three years so it builds a strong root system and a dense base. From then on, trim lightly in late winter, cutting the sides at a slight batter — wider at the bottom, narrower at the top — so light reaches the base and the hedge does not go bare and leggy. Never cut a native hedge between 1 March and 31 August, both because of nesting birds and because you will remove the blossom and berries that make it worth having.

Expect salt burn on the windward face after gales; this is normal, and hawthorn and blackthorn will regrow through it. Rowan may need a little extra shelter for its first few seasons — a temporary netting screen on the seaward side works well.

Gardening in the Lee

Once the belt is knitting together, usually by year four or five, you will notice the difference immediately: soil warms earlier, tender foliage stops scorching, and plants you had written off as impossible — hydrangeas, escallonias, even a sheltered fig — suddenly thrive. Use the calm zone nearest the hedge for your most delicate subjects, and let the outer edges of the garden adapt to whatever wind remains.

Plant a native windbreak and you are not just protecting plants. You are building a small, living piece of the coastal landscape that will outlast most of what you put around it.