7 Xeriscape Principles For Your Tasmanian Garden
Updated: Jul 2, 2020
Did you know that Hobart is Australia’s second driest capital city, averaging only 626 mm of rain per year? By following Landscaping Hobart’s guide to Xeriscaping, you can create a water efficient, low-maintenance garden using Tasmanian local native plants that complements Tasmania’s natural beauty.
What is Xeriscaping?
Xeriscaping (also known as Zeriscaping, Zero-scaping or Zeroscaping) was invented by Denver Water in 1981 and is the practice or process of designing garden landscapes in a way that eliminates or reduces the use of water.
The word “Xeriscape” is pronounced as “Zer-i-scape” and was coined adding the Greek word for “dry” (Xēros) as a prefix to the English word “landscape”. Xeriscaping is most popular in regions of the world that experience drought, with poor water supply or where water prices are especially high.
According to Denver Water’s Landscape Handbook, the goal of Xeriscaping is to organize high- and low-water-use plants tomaximize watering efficiency and create a landscape that’s sustainable in Colorado’s dry climate. You might ask, how Xeriscaping is relevant toTasmania? Well, did you know that Hobart is Australia’s second driest capital city (the first being Adelaide, South Australia)? Hobart only receives an annual average of 626 millimeters of rain, whereas the west coast of Tasmania receives anannual averageof 2,400 mm of rain.
The advantages of Xeriscaping
1. Save water
Xeriscaping uses xerophytes, beingdrought resistant plants that have adapted to arid climates. The use of these xeriscape plants in your garden means reduced watering frequency. In fact, a Xeriscape front yard will require 60% less water than a traditional lawn-based garden. This will not only reduce your water bill but also assist in replenishing your localrevivors, treatment plants and groundwateraquifers. Landscaping Hobart believes that saving water is important because “Australia is the driest inhabited continent on the Earth and, per capita, is one of the largest users of water in the world.”
2. Reduced maintenance
Xeriscaping involves replacing plants with high water needs (i.e. tropical and exotic plants, annual flowers and grass lawns) with Xeriscaping materials such as granite rocks, gravel, wood chips, pathways, timber decking, patios. All of these require no water, mowing, weeding, mulching or pruning whatsoever. A Xeriscape garden that requires less maintenance is a garden that saves you time and money.
3. Less green waste
Not all local councils in Tasmania offer residents a green bin used in the recycling of yard trimmings such as grass clippings, leaves, hedge trimmings, weeds and fall branches. This means that residents often have no choice but to dispose of green waste in a way that is not recycled, resulting in approximately 6.7 million tonnes of green waste was sent to landfill in Australia between 2016 and 2017. The issue is that when green waste decomposes in landfills, it releases landfill gas comprising approximately 55% methane – a greenhouse gas responsible for global warming. By Xeriscaping your garden, you can reduce the amount of green waste which your household is responsible for producing and so do you part in stopping global warming.
Using local native plants in your garden is a key aspect of Xeriscape design. For more information on Tasmanian local native plants, visit Landscaping Hobart’s guide on How To Use Native Tasmanian Flowers in Your Garden. Tasmanian local native plants have adapted to local conditions, meaning that they will:
resist damage from common diseases, fungal infections and pests without the need to use harmful pesticides; and
require little to no nitrogen and phosphorous fertilizer after planting.
While fertilizers and pesticides are often considered essential to gardening, during periods of heavy rain or watering, any excess water not absorbed into the top soil can run into local waterways (lakes, rivers and streams), carrying those fertilizers and pesticides with it. Fertilizer and pesticide run-off can degrade water quality and causes outbreaks of coral-eating crown of thorns starfish in the Great Barrier Reef, being a key contributor to the decline of coral cover across the Great Barrier Reef. The same applies for the Great Lake in Miena, Tasmania. You can help us save our local waterways by using a Xeriscape design in your very own backyard.
The disadvantages of Xeriscaping
You should be aware of the following disadvantages of xeriscaping:
many of the Xeriscape garden plants have prickles, thorns or rough leaves which could harm smaller children or pets;
although cheaper in the long term, the initial design and construction phases of Xeriscaping are expensive;
unless synthetic lawn or instant turf is used, the resulting landscape will often lack colour; and
there will be less soft ground surfaces which are typically used for sports and other recreational activities.
The 7 principles of Xeriscaping
1. Planning and design
Using pieces of graph paper, draw to approximate scale a:
site plan, showing the zones of your property, (e.g. house, driveway, garden path, flower garden, lawn and pond);
conceptual plan, showing the characteristics (e.g. sun exposure, shade, wind tunnels or soil types) of each zone and how you intend to use those zones (e.g. entertainment area or wildlife area); and
planting plan, showing the mature size of plants in each zone of your concept plan.
Refer to Xeriscape Principle 2 for more information on what plants to incorporate into your planting plan.
2. Plant zones
When drawing your planting plan, remember that different zones receive differing amounts of water, sunlight, shade, wind and moisture. All of these factors affect the amount of water plants in those zones will require. To conserve water, implement the practice of “hydro-zoning”, being the grouping of plants with similar water needs. You should:
place high water-use plants together in zones that are low-lying, shaded, protected from winds and naturally collect water; and
place low water-use plants together in zones that are dry and sunny.
You can use the Australian Plant Common Name Database provided by Australian National Botanic Gardens to search for inspiration. Before you start, visit Landscaping Hobart’s Guide to Using Tasmanian Local Native Plants in your Garden.
3. Improving the soil
You need to get your soil tested. Longley Organic Farm does soil tests from $310, excluding GST. A soil test will tell you exactly what your soil is deficient in and what you need to do to improve it. After you have the results of your soil test, you will need to break up the top soil to a depth of approximately 15 cm. Deep spading, plowing and rototilling with a garden rake or plow will aerate the top soil allowing plants to grow deeper roots. While you are doing so, add whatever organic matter was recommended by the soil test (e.g. decomposed bark compost or a mixture of soil and manure) to a depth of 5cm.
4. Re-thinking lawn areas
Did you know that lawns consume up to 90% of the total water used in residential gardens? Reducing the size of your lawn area (or replacing it entirely with synthetic lawn) is the easiest way to reduce water usage and time spent mowing, weeding, edging and fertilizing. Instead of using lawn as a means to fill empty space, only use lawn for a specific purpose. For example, lawn is perfect for a play area for children or as a visual frame for a zone. If you insist on using lawn, be sure to:
only sow your seeds during spring raids and avoid doing so in summer; and
use a native grass type such as weeping grass (microlaena stipoides) or wallaby grass (austrodanthonia spp).
5. Install an efficient irrigation system
Avoid watering by hand and instead install an automatic watering system which:
has a timed function to avoid watering between 10 AM and 6 PM;
has multiple but shorter watering periods (e.g. 15 mins at 6AM, 15 mins at 6:30 AM, and 15 mins at 7:00 AM;
only uses gear driven rotor sprinklers for lawns and spray, drip line or bubbler emitters for everything else; and
waters zones with different watering needs in different amounts.
6. Use of mulches
Mulch is not the same as compost and is a layer spread on top of the top soil as a protective cover and unlike compost, should not be tiled into the soil. Mulch will suppress the germination of weeds, retain water, insulate the soil from heat and reduce erosion. Simply remove all weeds and spread 8 to 10cm of mulch onto the top soil, making sure to:
mulch the entire root zone of each plant out to the leaf canopy; and
avoid mulching within 3 to 5 cm of the trunk.
7. Propper Maintenace
After you have created your Xeriscape, you can help it flourish by:
mowing lawns using the maximum height setting and leaving any clippings on your lawn to decompose;
weeding your flower beds consistently to ensure that important nutrients are not diverted away from your plants;
top dress your garden during rainy seasons with a small amount of organic fertilizer or compost; and
prune your plants conservatively during the winter season.
Looking for help creating your Xeriscape garden? Contact Landscaping Hobart by emailing firstname.lastname@example.org or using the Quote page.