Johannesburg – With the recent heatwaves and little rain, our gardens are being baked dry.
Parts of my lawn look like savannah, and many Joburg residents with vegetable patches have forlornly given up on them.
I’ve been watering my veggie patch after dark, but my grass is gone, says laments Northcliff resident Cheryl Hunter. Parktown North resident Dianna Games says she has been watering only parts of her garden that really need it. “The rest survives with whatever rain we get, or not,” she says.
On average, watering your garden uses up half your household’s water consumption every month (along with toilet flushing), so if you’re a concerned citizen doing your bit to save our water resources, the garden is your natural focus point.
Starting with the lawn, Mike Rickhoff from Lifestyle College of Landscape Design suggests you don’t be too precious about it. “We are in survival mode. Keep the lawn alive by all means, but look after the more expensive planted beds as a first priority. And in the medium to long term, think about shrinking the lawn,” he says.
Be practical about sprinkling, he adds. “Consistent coverage is key. Divide your entire watering space into a set of areas. So if you allow one hour of sprinkling time, you may have four zones of 15 minutes each to achieve full and even coverage,” he says.
To protect water evaporating quickly from your soil, compost (chopped up leaves or composted manure) is key. “A good layer of compost really works to save water. Groundcover plants are also a good way to cover drought-stressed soil,” advises Bronwyn Beyzel, nursery manager for Abacus Gardens in Johannesburg.
Not least, use 3cm to 5cm of mulch. “Mulch can be organic (bark, nut shells, peach pips, off-the-shelf mulch mixes) or inorganic (pebbles and gravel). Mulch holds moisture, prevents evaporation and keeps the ground temperature cooler for the plants. More mulch means less water. An added spin-off is weed suppression,” says Rickhoff.
Once your soil is nice and loamy, and if you’re planting, go for indigenous plants as much as possible. Succulents are ideal, including aloes, rock roses and cacti. “Once they’re established, indigenous plants don’t need to be maintained. They can survive on seasonal rainfall,” says Beyzel.
Tropical plants that require constant moisture are thirsty and will always struggle in drought conditions, adds Rickhoff. “Certain plants from damp, temperate climates will also need extra TLC during these harsh conditions. On the other hand, plants that thrive in the Mediterranean climate as well as many Australian plants tend to do well in hot, dry conditions,” he says.
Grouping plants according to their water needs is the water-wise way. “Group high water-using plants together so that they can receive the water they need, while low water-using plants can be similarly grouped and receive proportionately less water,” says Rickhoff. Beyzel suggests grouping the annuals in pots, as they need more water than perennials.
When it comes to watering, there’s a more efficient tool than a sprinkler, which sends water up mostly into the air. Drip irrigation and soaker hoses or watering tapes (hoses with slow dripping holes in them) minimise evaporation, and the water seeps out directly into the soil to the plant roots while keeping the areas between plants dry, which also limits weed growth. “Drip irrigation and soaker hoses are far preferable to sprinklers, and you can find them if you Google,” says Beyzel.
Finally, you can give yourself top marks if you harvest bath or washing machine water (greywater), using it to water your plants. “Used water is perfectly fine, as long as the soap used is biodegradable,” says Beyzel. Thus, don’t use kitchen sink, dishwasher or toilet water for irrigation.
A word of caution here: Continuous use of greywater in a single area should be avoided. Alternate the use of greywater in different spaces over time, says Rickhoff.
Tips from Rand Water’s Waterwise campaign:
* Water dry spots individually, and avoid wasting water by watering a large area if the intention is just to water a single rose or a small section of grass.
* Water if the soil in the root zone feels dry and crumbly, and if it looks as though the plant is starting to wilt.
* Watering in the late evening and early morning is best. Watering in the day results in loss of water through evaporation.
* Lawns are best watered in the mornings to help prevent disease.
* Sprinklers with coarse low spray are best. Fine high-pressure systems lose water when the droplets atomise into the atmosphere.
* Make sure your selection of irrigation nozzle suits your pressure.
* Water trees individually, giving them a deep drink but less often.
* Water slowly to prevent run-off but long enough to penetrate the root zone. By over-watering, water penetrates beyond the reach of the roots, and excess water will run off and be wasted.
* Check water connections for leaks.
* Switch off irrigation before puddling starts.
* Flowers and vegetables need short, frequent watering, while shrubs and trees need deeper but less frequent watering.
* Never water paving. Use a broom to sweep hard surfaces, not a hose.
* Use a lance for reaching hanging baskets and the back of beds.
* Avoid spraying in windy conditions.
* Use a watering can for window box plants, using the point to get to each plant individually. Don’t use the hose as this wastes water.
* Cut down on high nitrogen-based fertilisers. Rather use fertilisers with high ratios of potassium and phosphorus. This will encourage plant cell walls to thicken, enabling them to cope better in drought conditions.
* In drought, leave the lawn and annuals till last, and save the prized older plants which are not easily replaced.