Growing Tough Herbs In A Windswept Coastal Garden

Why Coastal Gardens Are Hard Work — And Why Herbs Cope

A garden within a mile or two of the sea is a bracing place to grow anything. Salt spray rides on the wind and scorches soft leaves, the topsoil is often thin and stony over sand or chalk, and the wind never quite stops. Plants that sulk inland — lavender slumping, basil blackening overnight — have no chance here unless you coddle them.

The good news is that the herbs we cook with most are Mediterranean by ancestry. Rosemary, thyme, sage and fennel evolved on windy limestone hillsides with poor, free-draining ground, and they treat a salty gale as a mild inconvenience. Plant them well and they will not only survive but scent the whole garden and keep the kitchen supplied from March to December.

The Four Workhorses Worth Planting First

Start with these and you will rarely lose a plant to the weather.

• Rosemary — the most salt-tolerant of the group. Upright forms such as 'Miss Jessop's Upright' make a dense 1.2 metre screen; prostrate types will trail over a low wall. It flowers in late winter, which is a gift for early bees.
• Thyme — common thyme and its lemon-scented cousins are perfect for the front of a border or between paving slabs. Creeping thyme will knit together gravel and shrug off being walked on.
• Sage — broad, slightly fuzzy leaves that hold up well in wind. Purple and tricolour forms add colour, though plain green is the toughest and the best for cooking.
• Fennel — a tall, airy plant with bronze or green feathery foliage and a deep taproot that finds moisture in dry ground. Give it space; it can reach 1.8 metres and seeds itself about happily.

Add winter savory, oregano and curry plant once these are established, and you will have a herb garden that looks deliberate rather than merely weather-beaten.

Planting Into Thin, Salty Soil

Drainage matters far more than richness. Herbs in thin coastal soil fail not because they are hungry, but because their roots sit in wet, sour ground over winter. If in doubt, plant high.

Dig a hole roughly twice the width of the pot but no deeper, and mix a good handful of horticultural grit into the backfill for every plant. On heavy or clay-tinged ground near a tidal river, plant on a mound 10–15 centimetres proud of the surrounding soil, or build a low raised bed filled with a mixture of two parts topsoil to one part grit.

Pot-grown herbs go in from early spring to early autumn, while the soil is still warm. Water them in well, then leave them alone. Avoid adding compost or manure to the planting hole — rich soil makes rosemary and thyme grow soft and floppy, and soft growth is exactly what salt-laden wind destroys.

A mulch of gravel or coarse shell grit around the base of each plant suppresses weeds, keeps the collar of the plant dry, and reflects light upwards, which helps ripening. Do not mulch with bark; it holds moisture against the stems and encourages rot.

Shelter Without Walled-Garden Expense

You cannot stop the wind, but you can break it. A solid barrier simply pushes gusts over the top and dumps them behind, so aim for something semi-permeable. A woven willow or hazel hurdle, a slatted fence, or a double row of hardy hedging such as griselinia or escallonia will filter the wind and cut its speed considerably.

Even a 60 centimetre high hurdle set a metre in front of a herb bed makes a remarkable difference. So does the simple trick of planting on the sheltered side of a shed, a wall or a mature shrub.

If your plot is a balcony or a windswept courtyard, containers are the answer. Use the largest pots you can manage — 30 centimetres across at minimum, 40 or more for rosemary — and choose terracotta or heavy stoneware so the wind cannot tip them. Raise them on pot feet so water drains freely, and group pots together for mutual shelter. A cluster of five or six herbs will come through winter far better than a row of isolated ones.

Watering, Feeding and Keeping the Flavour

Established coastal herbs need very little water; deep, occasional soakings are far better than a daily sprinkle, which encourages shallow roots. In the first summer, water new plants weekly in dry spells. After that, only water in a genuine drought, and water in the evening so less is lost to wind.

Feeding should be minimal. A light scattering of a general-purpose granular feed in early spring is plenty. Overfed herbs grow lush and taste bland; the intense oils that give rosemary and thyme their punch develop in lean, sunny conditions. West-facing coastal gardens often get excellent light, so make the most of it.

After a gale, hose down foliage with fresh water if you can — a quick rinse shifts salt deposits from the leaves. This matters most for containers, where salt accumulates in the compost.

Pruning, Harvesting and Winter

Harvest little and often, taking the top few centimetres of soft growth rather than hacking at old wood. Rosemary and sage will not reshoot reliably from bare, woody stems, so never cut back beyond the leafy growth. Trim lightly after flowering to keep plants bushy and to stop them splitting in the wind.

Fennel is cut to the ground in autumn, or left to stand for its seed heads if you want them for the kitchen. Thyme benefits from a tidy in early summer after flowering; leave it too late and the new growth will not harden before frost.

In exposed spots, protection in the first winter is worthwhile. A loose wrap of horticultural fleece around a young rosemary, or a windbreak of bracken fronds pushed into the ground around pot-grown herbs, will see them through the worst of it. Move smaller pots against a house wall and stand them on a piece of wood or a paving slab to keep roots out of standing water.

Do those few things and your coastal plot will give you scent on the wind, evergreen structure through the grey months, and more than enough leaves for a Sunday roast.