Weekend Argus (Saturday Edition)
Winning ways to save water
Here are some useful tips for gardeners to irrigate more efficiently in their gardens amid strict water restrictions over the hot, dry summer months, writes KAY MONTGOMERY
POOR winter rainfall and the likelihood of a hot and dry summer spells doom for your garden.There are various measures gardeners can take.
Plants may be watered with a bucket or watering can, but no hosepipes or irrigation systems may be used. Although watering times are not restricted, the city urges gardeners to water in the morning and evenings.
No watering is allowed within a 24-hour period after rainfall that provides adequate saturation. If you have a borehole, or make use of spring water or a well point, you are not exempt from this rule. All well points and boreholes must be registered with the city and used efficiently to avoid wastage and evaporation.
Drinking water may not be used to hose down paving and driveway areas. Ornamental water features may only be operated with recirculated water or a non-potable water source, such as harvested rainwater. The manual top-up of swimming pools is only allowed if the pool is fitted with a pool cover to cut down on the rate of evaporation. Gardeners have no choice but to implement steps to make their gardens more waterwise. This does not mean that you have to settle for a dull, uninspiring space, but rather adopt ways to use water more efficiently.
Firstly, determine the type of soil in your garden. Sandy soil is generally nutrient poor and suitable for fynbos. In very dry weather, clay soil dries out, so add plenty of organic matter to improve texture, drainage and break up hard clumps.
After planting, apply a 10cm thick blanket of mulch around plants, but keep it away from direct contact with the stem. This helps to retain moisture in the soil and prevent evaporation. Compost, bark chips or peach pips are all suitable mulch materials. Also plant groundcover to cover exposed soil and keep the beds cool on hot days.
Save water from baths and showers to use in your garden. Grey water can also be used on vegetables as the soap acts as a natural repellent for pests. When using grey water, give plants an occasional “flush” with rain or potable water. Do not use grey water on proteas, ericas and acid-loving plants like azaleas or camellias.
Consider installing a rain water tank before the next rainy season. This is an investment for your garden and can be a lifesaver during very dry spells. Place a bucket under downpipes to harvest rainwater run-off for containers on the patio. Plants that are indigenous to your region are an excellent choice as they are well suited to coastal conditions. Other drought-tolerant, non-invasive plants from countries with a hot, dry climate may also be included in a water-wise garden.
Some plants have certain characteristics which help them use water more efficiently. Plants with a sturdy internal structure support the leaves and prevent wilting during hot weather. Some plants drop their leaves during drought periods. Leaf shape, colour and texture may also help the plant use water more efficiently.
Small or thin needle-like leaves have a reduced surface area, which helps to minimise water lost to evaporation. Plants in this category include ericas, acacia spp., thyme, rosemary and buchu ( Agathosma spp.)
A wavy coating over the leaves helps to prevent moisture loss. Choose plants like kalanchoe, euonymus, ficus spp. and the Natal plum ( Carissa macrocarpa).
Hairs on the leaves help to slow down air movement across the leaf surface and reduce the amount of water loss. Plants in this category include lamb’s ear ( Stachys byzantina), buddleia spp, beach salvia, zonal pelargoniums, helichrysums, silver tree ( Leucadendron argenteum) and featherhead bush ( Phylica pubescens).
Plants with silver or grey foliage reflect the sun’s rays away from the plant and keep it cooler, with less moisture loss. These hardy plants include lamb’s ear, hebe, arctotis, Artemisia spp. and lavender.
Succulents like vygies, echeveria, aloes and crassula store water in their thick, fleshy leaves and the plant is able to utilise it when required.
Zone areas of your garden to create spaces where plants with similar water needs can be placed together. Look out for plants at your local nursery marked “One Drop” and “Two Drop” – these plants have low to medium water requirements.
Succulents like aloes and vygies with their bold structures and bright flowers are popular “One Drop” candidates for rockeries or low water zone areas. Between 30 and 60 percent of the garden can be designed for this zone, with around 20 to 40 percent making up a medium water zone. High water zones for “Three Drop” plants should ideally be around 10 percent, but not exceed 30 percent of the total area.
“One Drop” plants to include are: agapanthus, arctotis, gaura, gazania, ivyleaf pelargonium, lavender, strelitzia, rosemary, marigolds, wild garlic, wild olive, Cape honeysuckle and vygies.
Once established, “Two Drop” plants like roses, duranta, freylinia, New Zealand flax, Mexican blood trumpet, dianthus, deciduous fruit trees and zinnia only need additional watering in very dry spells during the rainy season and once a week during in the dry season.
“Three Drop” plants are best planted in containers close to the home where their water requirements can be monitored. These plants include fuchsias, azaleas, white arums and camellias and generally require water every two to three days.