Which Plants Are Best For Coastal Gardens?
We do like to be beside the seaside
Our beautiful beaches are a playground for all of us, whether we’re swiiming and surfing, building sandcastles with the bubs, or taking a stroll. Living by the coast is relaxing and energising, but can be hard on our garden plants.The wind dries out their foliage and stunts their growth. There’s often not much shade. Salt spray coats the plants’ leaves, preventing them transpiring easily, and seeps into the soil. Soils are often sandy, dry and very free-draining, as well as salty.
So what can we grow at the seaside that will thrive and look good in these harsh conditions?
Lifesaving plants for coastal gardens
If you have a dream ocean view, but a nightmare garden, choosing the right plants can help you to rescue it. We've got a whole category of Coastal Plants to help you choose; and they almost all have attributes in common.
Good plants for coastal locations have:
- silver-grey foliage - deflects scorching sun
- slender grass-like leaves – let the wind blow through without shredding the foliage and creating a tatty mess
- thick fleshy leaves or leathery leaves - they hold water and don’t dry out so fast
- a naturally low shape - aerodynamic in a strong breeze
Coastal rosemary (Westringia) gives you a clue in its name that it will grow just fine by the seaside. Small grey-green leaves cope well with bright light; and the naturally-rounded form can hunker down in a strong wind. It clips nicely to topiary shapes if you like a neater look. The Mediterranean kind of rosemary is just as resilient by the sea, along with other ornamental herb plants from the region, like thyme, oregano, and sage. New leaves of New Zealand Christmas bush (Metrosideros) are soft lime green, contrasting with older silver-grey leaves. In summer, the plant bursts into pompoms of bright vermilion blossom. It makes an excellent windbreak and privacy screen. Fiji Fire is lower-growing, ideal for hedging; thomasii is taller and denser if you need more protection. Gazanias are fantastically good in salty sandy soil. You can see these cheerful daisy-flowered plants growing right along the side of jetties where they are regularly drenched in surf and blasted with sea winds. We have yellow and white and pink and orange and mixed colours in season, all of which have fine leaves (some of them very silvery) and bright starry flowers.
Grasses grow great at the coast; those strong winds blow right through the fine leaves. Many grasses are used for erosion control which means they’ll hang on in slippery, free-draining, dry soils. Mat rushes (Lomandra) are well known for their soil-holding capabilities, and they are tough as an old Akubra.The lovely and hardy flax lilies (Dianella) double in height in full flower, with slender stems of dainty blue starry blooms. In other months their slender foliage looks fresh and elegant. There are very different kinds from white-striped Silver Streak to tiny Little Jess to purple-grey Utopia. Try our native club rush (Ficinia nodosa) too - it will grow in pure sand in the dunes alongside a beach. You might not think of waxflowers (Chamelaucium) as grass-like, but those needle-like leaves cope with hot sun and drying winds, and many waxflowers grow in very sandy soil in the wild. Taller bushes can act as a windbreak for a garden, sheltering more vulnerable plants.
Coastal banksia (Banksia integrifolia) lets you know in its name it’s happy at the coast. It may get to 20m, but most are much shorter. The leathery leaves are silver-grey underneath, very pretty when the breeze blows. Primrose yellow flowers appear in late summer through to winter.
Saw banksia (Banksia serrata) needs good drainage, making it well worth a try. It may only reach 2m, it may romp away to 12m. Whatever height you let it get to, the zigzag leaves and chubby cream-yellow flowers look good from summer to winter.
Low growing groundcover plants are ideal for seafront locations. They don’t mind strong winds, and cover soil with a living mulch, to limit water evaporation and topsoil drift.Queen of all is probably Carpobrotus, affectionally known as pigface, whose vivid magenta flowers dot the dunes and appear impervious to sand, salt, and sea breezes. Woolly grevillea (Grevillea lanigera) has leaves unlike many other grevilleas. Tiny, chubby, and covered in tiny silvery hairs, they keep the plant fresh in dry situations and warm in cold temperatures. Mt Tamboritha is low-growing, far-spreading, with dainty nectar-rich pink flowers through the year that birds and bees will love. Even the smallest outdoor space can find room for the cut leaf daisy (Brachyscome). It’s dainty-looking, with cute little lilac flowers, and it’s sturdy too. Cupheas, with their low spreading stems, can weather a storm and bounce back to fill the garden with butterfly-attracting blooms. For humid and subtropical coasts, coastal boobialla (Myoporum ellipticum) is ideal. With tiny fleshy leaves, and little white flowers, this plant even grows in tidal wetlands - so for wetter soils it’s a great solution.
All Purpose Plants
For steep slopes and exposed places you can't go past Agapanthus; they'll bind together a bank and need almost no care. Choose sterile named cultivars that won't self-seed if you're in a bushland area. Their jumbo-sized lookalike, the native crinum, also doesn't mind a sandy soil. In fact it doesn't appear to mind anything much, and is very resilient and adaptable providing it has access to regular water.Whether you’re after rockery groundcover, feature trees, or tall screening plants, Juniper is your answer. Tall slender Spartan makes a deep green privacy screen; slow-growing silver-blue Pyramidalis keeps a neat shape and a small height; and the gold-leaf form of lowgrowing shore juniper,All Gold will cascade happily over a rockery or retaining bank.
Top Tips For Growing In Sandy Soils
If you have sandy soil, you may think nothing will grow well in it! That couldn’t be further from the truth.Sandy soils are free-draining, making them easy to dig and plant in, and they don’t get waterlogged. If you live somewhere prone to frosts, you can start gardening in Spring much earlier than gardeners with clay soils. Sandy soils do benefit from improving, to help nutrients and rainfall stay in longer. If you enrich your sandy soil texture with organic matter like cane straw, well-rotted manure, spent mushroom compost, or homemade compost, that will go a long way to helping to hold in water and nutrients, giving your plants the best start in life. There are also a couple of things you can do when planting out, that will give plants a jump start.
- Dig a big hole, twice as wide and deep as you’ll need. Add generous amounts of compost or organic matter to the hole.
- Plant into the centre of a small dip. That way any rainfall or irrigation water will drain towards the base of the plant.
- Backfill the hole with the dug-out soil and lots of added compost. Mulch generously around, leaving a hand’s width gap from the mulch to the plant’s stem/base.
PS If you're at the beach, remember that Aussie Lifesavers rescue 35 people a day around our coasts. Stay safe out there. #swimbetweentheflags