Seaside gardens present their own challenges, but there are plants that will thrive in this unique climate
On our recent annual family holiday to the Roseland peninsula, in Cornwall, I spotted the owner of an intriguing coastal plot and invited myself for a look around; somehow, this is just about acceptable with gardens, while it would be rude to ask to look inside a stranger’s house. The garden turned out to be even better than I’d hoped and delivered interest far beyond its small size suggested. Here, on a series of terraces, steeply stepped and becoming more diminutive with each tier — like an inverted wedding cake — was a stunning garden, with the lowest terrace clinging to the rock just a few feet above the sea.
I was impressed, not only by the knowledgable owner, but with the array of plants within such a small space. Some I’d never consider trying in landlocked north Gloucestershire, while those that do grow back home — albeit with polite trepidation — were charging away here with wild abandon.
My host addressed the issue of overabundance. “The valerian grows like a weed; we pull it out in handfuls. As does the Erigeron karvinskianus and agapanthus. The echiums are over now, but they’re everywhere too.”
I, on the other hand, admired the overall lavishness of leaf and flower, and the neat overlapping mounds of echium foliage — still handsome enough to be cherished long after the towering spikes of flowers have faded — and sighed wistfully.
When you live far from the sea, it’s easy to forget that we are an island with (according to Ordnance Survey) more than 11,000 miles of coastline — though a bit of research shows it’s impossible to get a clear answer on this, depending on whether one includes the numerous islands, and how high the tide is. Whichever way you look at it, though, it’s a lot of seaside. Yet, for the most part, when thinking of coastal gardens, the mind of the average landlubber conjures up a narrow selection of default images of palm trees in Torquay and genteel carpet bedding in Blackpool.
In reality, our coastline comprises a broad range of geological features and growing conditions with every extreme variant of soil, exposure and climate. Often these defy the stereotypes: many parts of northern England and particularly the Scottish coast are blessed with gloriously unspoilt sandy beaches and comparatively balmy conditions, while the Kentish coastline can be relentlessly exposed to salt-laden gales.
One frequently hears the term “microclimate” applied to coastal gardens, with many claiming to occupy a uniquely sheltered cove benefiting from the Gulf Stream. Natural microclimate or no, you can create your own version, and thereby more shelter, by planting a windbreak of suitable hedging plants and trees, if you have room for them. This is preferable to a solid structure, which can create undesirable turbulence behind the barrier. Planting screens and filters reduces the effects of strong winds without blocking them entirely.
As anywhere in the UK, the right plant will thrive in the right conditions. Hence the familiarity of, say, fuchsias, which are often seen in coastal gardens, because gardeners have long known that they work. The resplendent camellias and azure hydrangeas in Cornish gardens are pretty commonplace to those who live there, and a sure sign of acid soil. Indeed, here, a reliably pink hydrangea would make a pleasant change.
While localised conditions vary across the UK, there are certain characteristics that make plants suited to most seaside gardens. Warm summer days belie the fact that most will also have to cope with the demands of life at the rock face year-round. Here, everyday challenges include buffeting by strong winds and salt spray, exposure to relentless sunlight and periods of low rainfall, coupled with thin, poor-quality topsoil. It needs a really tough cookie to thrive in these conditions, particularly in the more extreme locations, where plant choice will necessarily be more limited.
I recall being taught at the English Gardening School to look for plants with maritima (by the sea) or littoralis (of the shore) as part of their scientific names. You will often find that plants with silvery foliage — which reflects the drying sun while trapping precious moisture close to the leaf by means of the tiny hairs that give the leaves their metallic sheen — are perfectly adapted to cope with many of these challenging conditions. Narrow leaves, or ones with a waxy coating or thick, leathery texture, are further adaptations that provide a defence against the elements, and are again often found in plants that thrive by the coast.
Those of us stuck inland for most of the year can still enjoy these plants in someone else’s garden. If you have a late-summer “staycation” on the horizon, explore some of our great coastal gardens while on holiday. And keep your eyes open for the wildflowers thereabouts. Chances are they will be very different to those you see back home.
What to grow Agapanthus ‘Loch Hope’: Many of us enjoy growing these perennials, planted in the garden, or filling a large container. This late-blooming form has bumper-sized heads of blue flowers. But agapanthus really come into their own in coastal gardens, particularly in the southwest, where they remain welcome, despite their numbers reaching epidemic proportions.
Armeria maritima: Sea thrift is a favourite of garden designers when creating a show garden with a coastal theme. Forming low-growing mats of slender foliage, topped with large quantities of small pink flowers through late spring and summer, it’s perfect for filling gaps between stones, or strewing through gravel.
Crambe maritima ‘Lilywhite’: This form of our native sea kale has large leaves with a glaucous blue-green hue and airy clusters of white flowers. It’s fully hardy, copes with salt-laden winds and low rainfall and is a magnet for bees. If you’re short of a vegetable, the flowering stems are tasty when blanched and eaten like sprouting broccoli while still in bud.
Crataegus persimilis ‘Prunifolia’: One of my favourite small to medium-sized trees in any context, this hawthorn also happens to be tolerant of salt-laden winds. Spring sees the appearance of clusters of small white flowers, followed by generous quantities of scarlet berries. And, as a bonus, the foliage takes on wonderful autumn tints.
Eleagnus× ebbingei: This useful evergreen shrub has tough, dark green leaves, with pale silvered backs, and small off-white fragrant flowers during autumn. It should cope where others fail to thrive, and is useful for creating a windbreak — either clipped to shape or left to take on its natural form — in the most exposed gardens, enabling you to grow less resilient plants within its protective wind-filtering screen.
Eryngium maritimum: If your garden is right on the beach, you’ll already be familiar with our native sea holly. Alternatively, try one of the many cultivated forms, which come in a range of sizes, architectural shapes and icy silver, blue and mauve tones.
Geranium maderense: The fabulous, elaborately dissected foliage of this giant among geraniums earns it a place in the garden without a single flower in sight. It won’t cope with a severe frost, so this is one for the balmy conditions of the southwest — where it’s widely grown — and other sheltered coastal gardens.
Griselina littoralis: The staple of many a seaside garden, this evergreen shrub will quickly form a backdrop of attractive fresh green foliage, and is the perfect foil for flowering perennials and bulbs.
Quercus ilex: The holm oak is a familiar tree of coastal gardens. A Mediterranean native, with thick, leathery evergreen foliage, it can either be allowed to grow into a large tree, or be clipped annually to make a wind-resistant hedge.
Rosa rugosa: Tough, thorny and able to withstand strong, salty winds and thin, sandy soil, this rose makes a magnificent hedge and can be grown to provide a windbreak that will be adorned with masses of intense magenta flowers through spring and summer. Don’t deadhead too many and they will be followed by large, bright-red rosehips in autumn.
Rosmarinus officinalis Prostratus Group: Many of the Mediterranean herbs will cope well in warmer seaside gardens, but I’m particularly fond of this rosemary, which has a prostrate, horizontal growing habit, keeping safely below the harshest winds and draping itself over walls, steps and paving stones, where its aromatic evergreen foliage — studded with small pale-blue flowers on and off through the year — will be very much at home.