What can I plant by the sea?
Any gardeners familiar with gardens in coastal situations will notice that they are either barren plots with a few struggling shrubs or gentle, billowing oases of foliage and flowers. The proximity of the sea is a mixed blessing. The winter is warmer than it is inland and in milder areas frost and snow may be rare. Light levels are high and there are few trees to influence the growing conditions. The natural flora of sea cliffs demonstrates how plants survive: they stay close to the ground and are adapted to the environment. Salt laden winds can play havoc with less resistant subjects; many plant object by shedding leaves, getting scorched or just refusing to grow.
Soil is often stony, sandy and well-drained; conditions can be dry in winter or summer; a benefit to well adapted subjects but an additional stress to the vulnerable. A shrub with waxy or silver leaves has more resistance to both salt and drought. The simple solution to success when planting a beach garden is to choose plants that thrive, rather than those that struggle to survive.
Seaside gardens have a certain character and atmosphere. If you do not live by the coast but yearn for this type of planting don’t despair. You can create the impression of a coastal garden in any open sunny position with the help of a few well-positioned timbers, gravel, pebbles and maybe some thick rope or other seaside accessories. This type of scheme suits contemporary properties and sunny courtyards. It could also be used on a balcony or deck using suitable containers: maybe with a sea-green glaze or rusted metal.
Plants for coastal conditions
In any seaside scheme I would start with silver foliage. Its shining reflective quality just captures the spirit of the sea and gives a great basis to build upon. Brachyglottis ‘Sunshine’ is a tough shrub that will grow anywhere. Its broad, rounded silver backed leaves and felted stems stand up to the toughest conditions. Regular pruning maintains a neat, bushy, mounded plant. Prune when the grey flower buds appear in spring. The brash yellow flowers are not pleasing and are best removed before they open.
Flowers for a saline environment
The cotton lavender, Santolins chamaecyparissus is altogether softer and gentler in appearance. It too is best cut back before flowering unless you grow one of the pale-flowered forms. Santolina rosmarinifolia ‘Primrose Gem’ has greener foliage and soft creamy yellow flowers. It is far more attractive in bloom, particularly alongside any of the lavenders.
The butterfly lavenders, Lavandula stoechas varieties are less hardy than the English lavenders. So in the dried, milder conditions of a coastal garden they are more likely to succeed for a number of seasons. Like many plants that resist desiccation these have highly aromatic foliage laden with oils. Brush the leaves and you will find their fragrance is of lavender laced with menthol and eucalyptus.
The silky silver leaves of Convolvulus cneorum are perfect surrounded by gravel or in a glazed container. The hair-like filaments that cover the leaf surfaces are wonderfully reflective making the foliage shine brilliantly in strong sunshine. The pure white, purple-pink backed flowers are equally dazzling. Although this is not the hardiest of subjects it is surprisingly tough on well-drained soil in a sheltered spot.
Planting a Mild Coastal Garden
In exceptionally mild areas the lovely Convolvulus mauritanicus is a must for any coastal garden. Sheltering at the base of a sunny wall or cascading from a terracotta pot its profuse sky blue flowers carried on slender trailing stems are an uplifting sight. In colder areas grow it as a seasonal container plant or protect it in winter. It seems to bring a little of the Mediterranean to cooler shores.
Hebes thrive in coastal gardens. The larger leaved varieties that often succumb to disease inland remain healthy by the sea as salt air chases away those fungal spores. The small-leaved varieties are nonetheless hardier and tougher and cope in more exposed situations. Those with steely grey-green leaves combine will with the softer leaves of silver foliage plants. Hebe albicans is a good example: a compact little plant forming a tight dome spangled with pure white flowers in summer. The tiny single flowers of hebes are laden with nectar and very attractive to bees and pollinators.
Although usually thought of as a woodland plant the common honeysuckle, Lonicera periclymenum is really successful in coastal gardens. You often find its fragrant blooms amongst the cliff top vegetation in Cornwall, south-west England. This climber will grow as a sprawling, scrambling shrub and like the hebe its fragrant blooms will be a magnet for bees and pollinating insects.
Shrubs for a Coastal Garden
When it comes to larger shrubs, in positions sheltered from salt spry the large flowered lacecap and mophead hydrangeas excel. At the valley garden of Trebah, Cornwall four acres of hydrangeas colour the summer in shades of blue, indigo and purple. They seem to reflect the tones of the sea in the cove below the garden: deep, dramatic and changeable.
For those of us living inland a layer of gravel and pebbles over the soil surface keep winter wet away from the plants and help to reflect light and warmth. Not only can a garden of this kind bring a little seaside magic closer to home, it can also provide a more favoured growing environment for these sun-loving subjects.