Johannesburg - ‘Water, water everywhere, only if we share”, was the slogan chosen in an international high school slogan competition for this year’s International Year of Water Co-operation and World Water Day (Friday, March 22).
Celebrated annually, World Water Week includes a range of activities through the world. In South Africa the focus is on educational initiatives and this year is dominated by a partnership between the SA National Bottled Water Association (Nestlé, SAB-Miller and Coca-Cola) and the Department of Water Affairs.
World Water Week is about gardening responsibly with water.
For many gardeners, this may mean discovering how to create a colourful, low water flower garden. For others, it involves investing in a grey-water system, developing a wetland, investing in an automatic irrigation system or discovering how to create a beautiful garden using only rainwater.
As gardeners, we can co-operate and still have interesting gardens. We can also create different water-use zones and group plants with similar water needs.
The principles to water-wise gardening are simple and can be applied to every new or established garden. The key is to think about landscaping your garden into water zones and protecting your soil from moisture loss.
Consider these ideas:
* Zoning. When buying plants, look for those marked as suitable for the different areas in your garden.
Moisture-loving plants are best placed on the south and east side of buildings and drought-tolerant plants on north and west-facing areas. Group plants that need the most water near the house and in containers on the patio for easy watering. Invest in a water tank for harvesting rainwater off roofs for use in dry periods. Slimline tanks don’t take up much space and are less noticeable in small gardens.
* Become a water manager. Irrigation systems can be zoned to water-loving plants more often than plants which need less water. Irrigation sprays work efficiently where plants of similar height are grown together. Watch out for shadow areas where there is variation in plant height. Drip irrigation or seepage hoses have proven efficient.
* Soil. A blanket of mulch spread 10cm-deep around plants, keeping away from the stem, will keep soil cool and moist, smother weeds that compete with plants for water and nutrients, and insulate plants from temperature extremes.
Organic mulches can consist of coarse compost, shredded bark, cocoa husks, nutshells or pine needles. Bark chips or nuggets are also suitable, being decorative and long-lasting.
* In the vegetable garden, plant closely and in broad rows, so that there will be less evaporation. If a shallow basin is made around newly planted trees and shrubs, and around vegetables such as tomatoes and squash, water will collect and slowly filter down to the roots.
* Lawn substitutes. While lawns can have their place in a garden, particularly as a play area for children and animals, there are gardens where they can be reduced and replaced with groundcovers, gravel, bark chips or nuggets.
Before spreading gravel or bark, level the area and lay down a weed-suppressing membrane.
Paved areas prevent water soaking into the ground, while any of the above will allow water to be absorbed into the soil. If paving is used, leave occasional spaces for rain run-off and plant hardy, water-wise plants such as dwarf aloes, arctotis, bulbine, festuca, gazania, lavender, rosemary, stachys, strelitzia, succulents and verbena.
* Groundcovers. The need to conserve water has encouraged gardeners to seek alternatives to thirsty lawns. There are many ways of covering the ground and many plants that are suitable as groundcovers.
They can form carpets and mats, spread by surface runners or underground roots, or grow in clumps and mounds to form a virtually impenetrable cover.
Look out for indigenous arctotis, gazania, osteospermum and lampranthus (vygie) which are effective when planted close together in well-drained soil and in a sunny position.
Groundcovers suitable for shade include Ajuga reptans, Barleria repens with rose-pink flowers, Chlorophytum comosum (hen-and-chickens) with green and cream strap-like leaves, Lamium maculatum cultivars and clump forming Liriope spicata (lilyturf) with grass-like green or variegated leaves and purple flower spikes.
* Indigenous. Finally, many of our indigenous plants grow with the minimum of water requirements and are ideal for water-wise borders. Water-wise gardens need to bulk up on agapanthus, arctotis, Barberton daisy, Bauhinia galpinii, bulbine, crassula, crocosmia, dietes, euryops, felicia, gazania, kalanchoe, mesembryanthemum, osteospermum, plumbago, scabiosa, Tecoma capensis, tulbaghia or pelargonium. - Saturday Star