It’s become commonplace to turn on the news and hear about remarkable weather events. Weather reports showed record-breaking warm temperatures well into the 30’s and 40’s in most parts of our country, the effects of drought on farming and the devastating destruction of flash flooding. At the end of October we experienced temperature of 44C, unprecedented for this time of the year, to be followed up with gale force winds and then the fires along the Garden Route.
Although gardeners are accustomed to coping with variable weather conditions, in some parts of the country warmer than usual summers and winters with below average rain have gone from the exception to the expected. Fundamentally, today’s climate is much different from that of 10 or 15 years ago. Recent estimates predict an increase in global mean temperature of 2.4 to 6.4 degrees Celsius by the end of the century.
In general, the changing climate is resulting in shorter spring seasons, while summer and autumn are lengthening. This can result in drought-like conditions which will cause the soil to harden into a crust, making it not only hard for water to be able to permeate but also more difficult for the soil to hold any water that it is able to absorb.
To offset drought conditions, consider adding organic compost: this enhances the condition of the soil by binding together particles which hold water and nutrients in place rather than letting the water pass through too quickly. This also gives the roots of the plant something to anchor to.
Mulching also helps retain moisture to protect the plants from drying out quickly. It also moderates soil temperature fluctuations, which helps prevent plant stress. Further, it protects the root systems of plants that may be otherwise pushed out of the ground by the natural expansions and contractions that occur in the soil as it cools off and heats up, and helps to keep roots cooler during high heat periods.
Some things to consider when developing a water wise garden are:
- Roses, vegetables, flowering annuals and bedding plants require a lot of water: minimize areas for planting these.
- Consider a succulent garden, you can create an attractive design by combining interesting leaf forms and colours.
- Lawns are water guzzlers: reduce the size of your lawn or replace with gravel or hardy groundcovers.
- Choose hardy shrubs, either indigenous or exotic. Some of our indigenous plants also suffer greatly in extreme heat and drought conditions, research the hardiness of any replacement plants before making a choice.
- Mulch the flowerbeds to minimise evaporation.
- Install a water tank.
- Give plants a good soak rather than a sprinkling every day.
The recent water restrictions in many parts of our country, and the alarming projections for water availability in South Africa, are wake-up calls to gardeners across the country. The availability of potable water in Knysna is of grave concern as we are totally dependent on the water flow of the Knysna river and its tributaries. We do not have a large enough storage dam to act as a back-up in the event of drought conditions.
It must be remembered that Knysna has had water restrictions in one form or another for many years. With increased developments and population growth our water resources can simply not cope with the demand. Water availability will further change in the near future, and we will all have to change with it.