Reading the Plot Before You Plant

A wharfside garden is a wonderful thing, but it is not a suburban border with a sea view bolted on. Before you order a single plant, give yourself a fortnight to watch how the wind moves across the plot. Which corner takes the brunt of a south-westerly? Where does the tide-driven rain actually land? Where does water sit for a day after a storm, and where does the ground go dusty and cracked by August?

Wharfside ground is rarely straightforward. You may be dealing with compacted hardcore from an old working yard, a shallow skim of sand over rubble, or soil that is alkaline and gritty with shell and salt. All of that is workable, but it changes what you plant and where. Note also the salt line: the height and distance from the water at which foliage starts to look scorched and browned. Anything planted seaward of that line needs to be genuinely tough.

Choose Plants That Earn Their Keep

Hardy perennials do the heavy lifting in a coastal garden because they die back, reappear, and ask very little of you once they have settled. Aim for a mix of silver, grey and leathery foliage, which reflects light and resists salt burn, with a few bold flowerers for colour from May to September.

• Sea thrift and sea campion for the front edge, where nothing else survives.
• Lavender, rosemary, santolina and thyme for scent and structure, provided drainage is sharp.
• Sea holly and sedum for late-season interest and seedheads that hold through winter.
• Hardy geraniums such as Geranium sanguineum for weed-smothering ground cover.
• Ornamental grasses — Stipa tenuissima, Deschampsia cespitosa and pheasant's tail grass — for movement and sound that suits a windswept site.
• For structure: escallonia, griselinia, hebe and tamarisk, all of which cope with spray and exposure.

Plant in autumn or early spring so roots establish before the drying winds arrive, and water generously through the first two summers. After that, most of these will look after themselves.

Gravel, Mulch and the Quiet Suppression of Weeds

If you take one piece of advice from this article, make it this: mulch with gravel, not bark. Bark blows about, holds damp against stems and turns into a weed seedbed within a season. Gravel, laid 50–60mm deep over a woven geotextile membrane, lets rain through, keeps root runs cool, reflects light up into the foliage and stops almost everything germinating beneath it.

Leave generous planting pockets cut into the membrane, and sweep the gravel back around stems after planting. Top it up every few years rather than replacing it. The same approach works beautifully around gravel-tolerant plants such as lavender and thyme, and it dramatically reduces the amount of time you spend on your knees with a hoe.

Raised Beds and the Question of Soil

Where the ground is thin, stony or contaminated by decades of fuel, oil and rubble, do not fight it. Build up. Raised beds of 30–40cm depth give you a controlled growing medium and save your back. Use a loam-based mix cut with horticultural grit and well-rotted compost — roughly two parts loam, one part grit, one part compost for most coastal plantings, and leaner still for Mediterranean herbs.

Timber is the usual choice for a wharfside plot because it suits the industrial-rural character of the setting. Line the inside with a membrane to slow rot, use stainless or marine-grade fixings, and sit the bed on a gravel drainage layer if the subsoil below is compacted. Raise beds on legs or plinths where the tide occasionally reaches. Troughs and large containers work equally well for herbs and annuals near the door, and they can be moved when the wind shifts.

Shelter, Structure and Screening

Wind is the single greatest challenge on a wharfside plot, and the instinct to build a solid fence is usually the wrong one. A solid barrier forces wind up and over, creating damaging turbulence on the sheltered side. A permeable screen — a hazel hurdle, slatted timber or a planted hedge with roughly half its depth open to the breeze — filters and slows the wind instead, so plants settle rather than thrash.

Combine a hard screen near the seating area with a planted windbreak of escallonia or griselinia behind it. A small wind-tolerant tree such as amelanchier, rowan or hawthorn gives height and a sense of enclosure without casting heavy shade. Position the most tender plants, and any seating, in the lee of these.

A Light Seasonal Rhythm

The pleasure of a low-maintenance waterside garden is that it asks for effort in bursts rather than constant attention. In spring, cut back ornamental grasses, top-dress beds with compost and check fixings and ties after winter gales. Through summer, deadhead to keep flowers coming and water new plantings deeply once a week rather than little and often — deep watering pushes roots down.

Autumn is planting time: get shrubs and perennials in while the soil is warm, and mulch with gravel or compost. In winter, clear blocked drains, cut back storm damage and keep off sodden ground so you do not compact it. Do that, and you will have a garden that looks after itself while you watch the weather come in off the water.