Successful coastal gardening
South Africa is known for its beautiful coastline, but with this comes quite harsh conditions for our plants and trees in these areas.
Many plants that grow happily in more inland, leafy suburbs will probably shrivel and die when exposed to the windborne salt, harsh light reflected off the sea, and hot dry summers associated with the Western Cape’s coast.
Fact is: plants in coastal gardens need to be tough! They have to withstand seasonal gale-force winds, resist the damage caused by salt-laden breezes and grow in sandy soils.
Plants selected for gardens at holiday homes also need to be able to endure periods with little water.
But this does not mean that coastal gardens have to be bleak and boring; quite the contrary, in fact.
The key is to understand your immediate environment and choose plants that will flourish in those conditions.
Sounds like a tall order?
Luckily there are attractive plants which fit the bill; pick the right ones and you’re sure to have success!
Let’s show you how and what to plant in a coastal garden!
Be realistic!
Even though you might love the dainty look of a Leopard tree or the beautiful flowers of a Clematis climber, if you are living near the Western Cape coast, the South-Easter wind will just blow it to pieces and it will never become great in its true form.
Rather plant the correct plant species for the correct conditions - than forcing a species to try to adapt to conditions that it can’t cope with.
Do some homework:
Knowing which plants to plant in your coastal garden will be the difference between your greens just “hanging on for dear life”...or thriving.
Hot, dry summers are a test of endurance for any garden, let alone coastal properties. It makes sense to choose plants that are climate-appropriate.
It’s best to choose either local, indigenous plants or plants from the Mediterranean area:
Mediterranean plant options:
lavender, olive, statice, pelargonium, Indian hawthorn, rosemary, westringia
Indigenous and local:
Members of the daisy family for instance, like gazanias, dimorphotheca, ursinias grow in sandy soil, tolerate wind, help stabilise the sand and reduce evaporation.
The West Coast is home to the most beautiful indigenous plants and every year attracts thousands of visitors who flock to see the veld turn into a rainbow of colour in spring
The sandy soil supports a wide array of flowering groundcovers, shrubs and perennials and even trees that can all be used in the coastal garden.
Besides their aesthetic value, most indigenous plants are less costly to maintain, largely because they have long adapted to the local climate and thus to the local rainfall – they are more cost effective in their water consumption and many have subsequently been termed “waterwise” plants.
By planting and growing indigenous species you are also helping to conserve our rich floral diversity.
IDEAL CHARACTERISTICS FOR COASTAL PLANTS:
Tough, leathery grey leaves
that reflect the heat and often have a protective covering of hairs.
Some examples of plants with these types of leaves are the coastal silver oak (Brachylaena discolor), mock olive (Buddleia saligna), and arctotis.
Leaves with hairs
slows down air movement past the stomata, which reduces water loss.
Examples: lamb’s ear, helichrysum, beach salvias
Leaves with a shiny or waxy coating
that reflect the sun, reduce surface evaporation and deflect salt.
Look out for them on plants like the white milkwood (Sideroxylon inerme), coprosmas, the carissas like the num-num, Indian hawthorn and succulents like cotyledons and aloes.
Tiny needle-like leaves
such as those found on buchus, coleonemas (confetti bush), rosemary and the fynbos ericas whose leaves roll up to reduce evaporation.
Succulents
store water in thick fleshy leaves:
Crassula, aloes, echeverias, and vygies.
Plants with lighter leaves on one side
to turn the lighter side upwards to reflect the sun away – when stressed.
Eg: wild olive, gazania, buddleja
Plants with a strong internal skeleton
support the leaf and prevents wilting during dry spells.
Eg: Strelitzia, restios, agaves
Trees for a garden with an ocean view:
Trees and tall growing shrubs will help control the heat on your property as well as acting as wind breakers.
Typically large trees very close to the beach don’t do well, because of the wind, but if staked correctly they can grow.
Keep in mind that factors such as prevailing winds, soil types, other buildings or trees (that offer screening) and how close to the sea you are located, must be taken into consideration when selecting trees (and plants in general) for your coastal garden.
Top trees for harsh coastal conditions:
- Sideroxylon inerme – Milkwood/ Melkhout
- Brachylaena discolor – Coast silver oak/ Kusvaalbos
- Phoenix canariensis- Canary Date Palm
- Phoenix reclinata – Date Palm
- Washingtonia robusta – Fan Palm
- Pandanus utilis – Screw Pine
Trees for milder coastal climate (rated from hardiest to less hardy):
- Plumeria rubra – Frangipani
- Buddleja saligna – False Olive / Witolien
- Vachelia (Acacia) karroo – Sweet Thorn/ Soetdoring
- Ficus rubiginosa – Port Jackson Fig
- Harpephyllum caffrum – Wild Plum/ Wildepruim
- Syzygium cordatum – Water Berry/ Waterbessie
- Syzygium guineense – Waterpear/ Waterpeer
- Syzygium paniculatum – Australian brush cherry
- Olea africana – Wild Olive/ Olienhout
- Ceratonia siliqua – Carob / Karob
- Trichellia emetica – Natal Mahogany/ Rooiessenhout
- Harpephyllum caffrum – Wild Plum/ Wildepruim
- Nuxia floribunda – Forest elder/ Bosvlier
- Aloidendron (Aloe) barberae – Tree aloe/ Boomaalwyn
- Vachelia (Acacia) sieberiana – Paperbark Torn/ Papierbasdoring
- Vachelia (Acacia) xanthophloea – Fever Tree/ Koorsboom
MORE TIPS:
- It is important to ask yourself what purpose your garden will have. Is it there for its aesthetic value, low-maintenance practical value, organic value, conservation value, or perhaps some other reasons.
- Before you decide on plant choices, examine the micro-climates in your garden. While windy conditions may prevail in one part of the garden, there may be a section that is actually quite sheltered, for example, directly next to the house. This allows for a greater range of plants in the garden.
- Remember that the more waterwise you make your garden from the start, the easier and cheaper it will be to keep it beautiful and maintenance free. If you are planning on incorporating some “less waterwise” plants, group these in an area close to your home so that they are easy to water regularly.
- When eastablishing a new coastal garden, one of the first things to do, is plant fast-growing groundcovers and scrambling plants to stabilise the shifting sand. Good choices are Carpobrotus, Arctotis and Gazania.
- Create protected pockets in the garden using reliable, hardy, wind-tolerant trees, shrubs and hedges as windbreaks as this will allow you to grow a wider range of more sensitive plants. (eg. Brachylaena discolor, wild olive, Searsia crenata).
- With a very steep coastal property, retaining walls and terracing is necessary. With less steep slopes a rockery is a possible solution.
- Mild slopes can be planted up using groundcovers and shrubs that have spreading root systems that help bind and hold the soil. Plectranthus species (eg. P. neochilus) make excellent groundcovers.
- A typical coastal garden mostly has sandy soil. This soil has little nutrient value and water drains quickly through the sand, instead of being “held” around the roots of plants. The best way to improve sandy soil is to put plenty of compost in planting holes and if possible, add water-retaining granules.
- Regularly applying a thick layer of organic mulch helps to maintain soil texture and slows down water evaporation from the soil during the hot, dry season.
- Plan to do most of your planting in late autumn at the beginning of the rainy season when it is not so hot, so that the plants have had time to establish themselves before the next dry summer season.
- Watering: Channel and collect rainwater from the roof of your house for watering your garden. Water early in the morning, in the late afternoon, or at night to reduce evaporation. Never water while the wind is blowing; this is wasteful.
- Group plants with similar water needs together and water these zones separately.
With some focus on design, planning, plant selection and planting techniques it IS POSSIBLE to have a beautiful outdoor space when you live at the coast!
Happy (coastal) gardening!