Plants in coastal gardens 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. This sounds like a tall order, but there are attractive plants which fit the bill; pick the right ones and you’re sure to have success.
Members of the daisy family, like gazanias, dimorphotheca, ursinias grow in sandy soil, tolerate wind, help stabilise the sand and reduce evaporation.
Your first priority is to create a windbreak that will give protection to your smaller, more delicate plats. . Once this is established, you can choose from a greater range of plants in the sheltered side of the garden. A windbreak can be constructed with hard landscaping or consist of trees and shrubs. A combination of both can be used successfully.
Windbreaks in the garden also protect the plants from salty sea spray. Do remember that these plants won't stay small forever though, so think carefully before you spend your hard earned money and then have to remove them because they are blocking your view.
Coastal homes mostly have 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.
While most plants prefer a loamy nutrient-rich soil, remember that indigenous plants tolerate sandy soil conditions. For fast-growing groundcover, plant Carpobrothus, Osteospermum fruticosum and Geranium incanum).
Suitable shrubs include Pink Mallow (Anisodontea scabiosa), White Confetti Bush (Coleonema album), Polygala (Polygala myrtifolia), Salvia (Salvia africana-lutea) and Waterberry (Syzygium cordatum).
Many coastal homes are on sloping sites which makes gardening difficult. With a very steep property, retaining walls and terracing is required while, 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 make excellent groundcovers.
Sculptural plants will add interest and texture to your planting. Consider the dune Aloes and Restios. Whatever you do, choose plants that are climate-appropriate. You could try the following plants: Pincushion proteas, Euryops daisies, Lavender, Pride-of Madeira, Statice, Pelargonium, Indian hawthorn, Rosemary, Cape Honeysuckle, Agapanthus, Arctotis,Senecio and Cistus.
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 Tarchonanthus, Brachylaena discolor, Buddleia saligna and 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 and Amatungulu Plums, and succulents like Cotyledons and Aloes. Tiny needle-like leaves such as those found on Buchus, Coleonemas (confetti bush) and the Ericas whose leaves roll up to reduce evaporation.
Group plants with similar water needs together and water these zones separately.
A layer of mulch over the bed will keep soil moist for longer, and adding compost increases organic matter which improves the soil’s nutrient level and water-holding capacity.
Small or needle-like leaves. This minimises the surface area for water to evaporate. Examples are ericas, most acacias, rosemary, origanum and thyme.
Few leaves. Some plants reduce water loss by dispensing with leaves altogether, or shedding during drought. Examples are the karee tree, acacias and buffalo thorn.
Grey foliage reflects the sun’s rays, keeping the plant cooler which in turn reduces water loss. Examples are lavender, artemesia, arctotis and giant honey flower.
Hairs slow down air movement past the stomata, which reduces water loss. Examples are the silver tree, lamb’s ear, beach salvia and helichrysum.
Succulents store water in thick fleshy leaves. Think of crassulas, aloes, echevarias and vygies.
The leaves of some plants close when they are water stressed. This reduces the amount of leaf exposed to sunlight and reduces water loss. Examples are acacias, Jerusalem sage and rock rose.
Waxy leaves prevent moisture loss. Examples are euonymus, kalanchoe and Indian hawthorn.
When ‘stressed’, plants with lighter leaves on one side, turn the lighter side upwards to reflect the sun away. Examples are wild olive tree, gazanias and indigenous buddlejas.
Plants with a strong internal skeleton support the leaf and prevents wilting during dry spells. Examples are strelitzia, restios, agaves and New Zealand flax.
Volatile oils in the stomata forms an extra protection against water loss. This is common in Mediterranean plants, an area which has hot dry summers. Examples are rosemary, lavender and sage.
An old faithful favourite amongst gardeners and landscapers. It is dependable, evergreen, drought hardy and fast growing. Plant it in the sun or semi shade and look out for the blue flowers in summer. These will attract butterflies and birds, which also use the bush as nesting sites. The flowers are edible and look pretty in a fruit salad or floating in a cooldrink. It responds well to pruning and if left to its own devices, it will scamper up to the tree tops.
Fast growing, evergreen shrub that copes well with drought conditions and wind. It can grow to 2m and responds well to pruning. There are many colours available now from yellow, orange, salmon, pink and red and they flower from spring through summer.
Aloes are a hardy, beautiful species that can be used as shrubs or as structural plants in water-wise gardens. Numerous species exist in South Africa, and a number of hybrids have been cultivated for the market. Care should be taken not to over-water aloes, which may increase their susceptibility to disease. Popular species include Aloe arborescens (krantz aloe), Aloe marlothii (mountain aloe), and Aloe ferox (bitter aloe).
Strelitzia’s height and structure add an architectural element to the garden. They can tolerate a fair amount of wind especially as one plant protects the next. Their succulent
roots help them survive dry periods and stabilise the soil, while birds are attracted to the nectar which drips from their ice blue and white flowers. They’re particularly good for the
warmer East Coast gardens. Height: 1,5–5m.
Gazanias are useful spreading groundcovers for coastal gardens as they are both wind and salt tolerant. Not only do they cover the sand quickly, preventing it from being blown
away they help reduce evaporation. Their cheerful bright yellow or orange flowers add colour from midwinter well into summer. Some varieties have dark green leaves, while others
have grey or variegated leaves as pictured below.
They are easy to grow from slips or rooted cuttings. At the seaside, they should be planted closer together than usual. Height: 20–30cm.