It may be one of the latest trends in gardening but xeriscaping is really just a fancy word for going back to basics.
From the Greek word xeros, which means dry, xeriscaping is the practice of using creative landscaping to conserve water.
This includes extensive mulching and putting in native plants that are suited to the climate so you don't have to water your garden all the time.
Xeriscaping is a term coined in the US to deal with drought-stricken areas but because it involves using ecologically-sound practices and results in a low-maintenance garden, it is becoming popular even in areas where there isn't a water shortage.
Given the rainfall we've been having in New Zealand lately, it would seem that we don't need to worry about a lack of water in our gardens. But remember how dry the summer was?
Landscaper Vernon Sweeney says he's been working in gardens pulling out dead exotic plants that were casualties of the rain shortage last summer.
"After a summer like we just had, people are having to think about plants that can handle it better," he says.
Sweeney, who works for Auckland firm Maintain It, is replacing thirsty plants with ones that can cope without lots of water, including native grasses. Doing this is one of the principles of xeriscaping.
In the meantime, he is also working on his first completely xeriscaped garden, outside the new National Bank in Blockhouse Bay.
The building is being constructed using environmentally sustainable practices such as collecting rainwater to flush toilets and putting in skylights to reduce the need for artificial lighting, and it will have a garden to match.
"We're using all New Zealand natives such as cabbage trees and titoki," says Sweeney. "They are very drought-tolerant and low maintenance."
The National Bank garden will also use a lot of mulch to keep moisture in as well as weeds out, and natural fertilisers, instead of those made with chemicals, which are good for the soil as well as the plants, he says.
"It's going back to basics the way gardeners used to garden in the past."
Xeriscaped gardens make good sense for offices and homes, as well as apartment buildings where people don't want to spend time tending to the plants. They're also ideal for roundabouts and traffic islands and many councils are already following the principles. Coastal gardens and those with poor soil that doesn't retain moisture such as volcanic soil would also benefit from xeriscaping, says Sweeney.
There are seven basic principles of xeriscaping:
Planning and design
Also known as hydrozoning, this involves putting plants with similar watering needs together. Plants that need more water can be put in a shady spot so they don't need so much water. You also need to be aware of the natural draining patterns of the land so you can make the most of rainfall. Your design should include techniques for harvesting water where possible, such as using mounds or berms at the edge of the property so water drains back into the garden.
Increasing the amount of organic material in your soil and keeping it well aerated will help it retain water, making it ideal soil for a water-conserving garden. Compost will help unless you are planning on planting lots of cacti and succulents, which prefer lean soil.
Limit lawn size
Keep grassy areas as small as possible. Ask your garden centre for drought-tolerant grass if you're planting a new lawn.
Use appropriate plants
For the best results, select natives. Choose ones that are drought resistant and need only a minimum of water. Remember that trees help reduce evaporation of water by blocking wind and shading the soil.
Covering the soil around your plants with a mulch, such as leaves, compost, wood chips, bark or gravel will help keep moisture in, prevent erosion and block out weeds. Mulch needs to be at least 6cm thick and applied twice a year.
Use a system like drip irrigation that delivers the water directly to the base of the plant. Spray systems can waste water if it goes on edges or paths where it is not needed.
Keep on top of maintenance
Xeriscaping is it gives you a low maintenance garden but you will still need to get rid of any weeds that pop up through the mulch.
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The benefits of xeriscaping include:
- Saving water resources so there's more water available for other uses - Lower water bills
- Less maintenance, so you don't need to spend as much time in the garden
- Little or no lawnmowing
- Plants that are more likely survive in times of drought
Plants suitable for xeriscaping include:
- Native flaxes and grasses
- New Zealand sedge
- New Zealand ice plant
- Astelias n Rock lily
- Cabbage trees
- Pohutukawa (go for dwarf varieties if size could be a problem)
- Plants that are drought-tolerant and low maintenance, but not native include yuccas, agaves and succulents. Anything that has leaves that are silver or grey, or have a slightly woollyfeel will tolerate a shortage of water.