One of the increasingly important aspects of garden design is the use of water wise plants to conserve water as well as to save money.
Waterwise or ‘Drought Tolerant’ Plants are sometimes perceived as ‘boring’, or thought to be limited to cacti and succulents. However when we research plants that can best cope with limited water, we actually come up with a range of great plants, perennials, bulbs, trees and shrubs.
The image of low water use ornamental grasses may not provide you with the colour you are looking for in the garden, however many plants with colourful flowers are also low water use, and Salvias are some of the best.
Most Australian Native Plants are ‘drought tolerant’ but so are roses, which cope with little water once established, if they are well mulched. Cliva and Daffodils do well on little water and Arbutus are a tough drought tolerant tree. Some nurseries identify and carry a range of waterwise plants, we list them below.
The Key to Water wise Plants
- Using plants in the garden is all about where you plant then, and by grouping plants that require similar amounts of water it is easier regulate watering patterns.
- A few natural factors also come into play. Plants in afternoon shade will generally survive with less added water. Those planted at the bottom of a slope, or even in a slight depression will naturally receive more runoff and seepage than others.
- Water wise does not always mean sun tolerant, some plants will grow exceptionally well in dry shade, however will not survive in full sun, other perform best in the sun.
- Using summer dormant plants, especially bulbs, can provide colour in spring or autumn without the need for summer watering.
If we are looking at trees, then one interesting species is the Water Gum, its an Australian native tree that in its natural habitat is found by creeks, however the Water Gum – Tristaniopsis laurina – is actually a tough tree that requires little water at all.
We then get to the obvious ‘water wise’ cantidates, the succulents, aloes, agaves, euphorbia, crassula and cacti.
What about water wise plants for the cottage garden
Try echium, and of course kniphofia, yarrow, renga renga lily and adenanthos, all fit well into the cottage garden scheme and all have low water requirements.
Water Wise Gardening Fact and Information Sheet
Some of the basics to waterwise gardening are mulch, deep watering, careful plant selection, positioning plants with similar water requirements near each other, Use of recycled water and tank water. Using shade trees to protect less tolerant plants and efficient water systems for irrigation and watering. Further information is set out below.
With water becoming a precious resource, gardeners are turning more efficient irrigation systems, water tanks, use of grey water, drought tolerant or waterwise plants and effective mulching techniques to keep gardens looking great. Gardens can be maintained in times of drought and here a few ideas to help you on your way.
IRRIGATION AND WATERING SYSTEMS
Start by replacing existing sprinklers and sprays with a drip watering system. Replacing the spray heads with drippers is not an expensive job and makes use of existing infrastructure. You might even connect your new drip system to a water tank.
WATER TANKS
A water tank connected to the roof of the average home will provide enough water to help keep a garden going in drought conditions. However, if simply connected to a hose you will use about 1000 litres in one hour, so connect to a drip system, install the largest tank you can afford (and fit) and maybe a pump to provide adequate pressure.
How much water does a water tank hold?
A water tank measuring 3.5m diameter by 2.2m height will hold about 20,000 litres, enough to keep your garden going for a while. However you can get tanks from 1000 litres and less to 250,000 litres and more.
Types of Water Tanks
Poly ( polyethylene) water tanks , metal tanks and concrete tanks. Poly tanks are the most popular in urban areas, with slimline tanks being popular as they can fit into spaces between the house and a fence.
Under-house systems, these can include small tanks or more flexible systems that are like large plastic bags in a metal frame, great if space is a problem.
GREY WATER
Grey water is water diverted from the laundry or bathroom, water from kitchens is not suitable.
Grey water is usually suitable for ornamental plants, it is not recommended for vegetables and care needs to taken when using grey water on native plants. If using grey water make sure that you choose detergents and laundry products with low phosphorous, sodium and nitrogen content. Grey water should not be stored for more than 24 hours and regular watering with fresh water is recommended to help lessen salt build up.
MULCH
Probably the most important factor, without proper mulch all of that water you saved and collected will evaporate fairly quickly.
Mulch slows evaporation and helps prevent the soil from drying out. Reduces watering by up to 60%
Prevents weeds from germination (weeds compete with other plants for moisture)
Mulch keeps the soil temperature constant and organic mulches adds organic matter as well.
How much Mulch? 2-6cms is a rough guide
What type of Mulch? Organic Mulch includ es, pea straw, bark, sugarcane mulch and many others.
Inorganic Mulch includes, gravel, pebbles and scoria.
A range of waterwise plants are available for sale from good nurseries
Our List of ‘water wise plants’ includes