Water Conservation Garden Did you know? A typical Melbourne home uses about 270, 000 litres of water in one year. About 35% of this goes on the garden. No wonder the garden is such a great place to start saving water!
The Water Conservation Garden at the Royal Botanic Gardens has been developed in partnership with South East Water Ltd to provide a model to demonstrate water-conserving landscapes that maintain exciting and diverse horticultural displays. 
A range of trees, shrubs, grasses and groundcovers are featured that are naturally adapted to dry conditions. Many grow well with little or no supplementary watering in Melbourne's climate. The plants originate from regions that have dry climates such as Africa, Australia, southern Europe and the Canary Islands. Most of the plants in the garden are readily available from local nurseries. Other characteristics of the garden include the use of an irrigation system with a low precipitation rate to reduce runoff and improve irrigation efficiency, and mulching to reduce water losses from evaporation. *Drought tolerant, warm-season turf grasses such as Kikuyu that can use 30% less water than cool-season grasses is used to provide definition of space and a foreground to the garden beds. The Water Conservation Garden is frequently used as an educational location for adult education, tertiary and secondary students, and visitors to demonstrate water-saving techniques and suitable plant selection. Since establishment, this garden requires about 50% less water than is normally applied to other well-managed irrigated garden beds in the Royal Botanic Gardens. In 2003, the Water Conservation Garden won the Sustainable Garden, Garden Design Category of the Savewater Awards www.savewater.com.au The Water Conservation Garden
This garden features trees, shrubs, grasses and ground-covers that are naturally adapted to dry conditions. They grow well with little or no supplementary watering. Many of the plants are native to Australia. Others originate from regions that have dry climates such as Africa, southern Europe and the Canary Islands. Most of the plants in the garden are readily available from local nurseries. The 3 Beds of the Water Conservation Garden  The following plants are an example of what specimens you will find at the Water Conservation Garden:
Bed 1
Echium aff. candicans
Euphorbia rigida
Alyogyne huegelii 'West Coast Gem' Bed 2
Armeria pungens
Anigozanthos 'Bush Gold'
Dampiera rosmarinifolia Bed 3
Chrysocephalum apiculatum
Anigozanthos 'Bush Splendour'
Euphorbia characias subsp. wulfenii Tips for creating a water-saving garden You can do a lot yourself! - Group together plants with similar water requirements.
Some plants need more water than others. By grouping plants with similar water requirements, you can help to prevent over- or under-watering individual plants. It can also simplify the design of a watering system. - Choose plants with adaptations that make them natural water conservers.
In general, plants with hairy, succulent, wax-coated leaves or with fine, stiff foliage (sclerophyllus) are adapted to growing in dry environments. Grey-or silver-foliaged plants are also usually suited to dry conditions. - Apply a layer of mulch annually to help minimise water-loss from the soil.
Mulch improves the long-term water-holding capacity of the soil and also restricts weed growth that may compete with plants for water. It should be applied in layers from 50-75mm thick. Mulch that is too thick can prevent rainfall and or irrigation from reaching the soil. - Consider replacing part or all of a lawn with groundcover or change to warm-season grasses.
Lawns can consume up to 90 percent of water in your garden. Warm-season grasses such as Buffalo, Couch or Kikuyu use water more efficiently and display *drought tolerance. These warm-season grasses can use up to 30% less water than cool-season species such as Ryegrass - Water deeply between the evening and early morning.
This is when evaporation from soil and transpiration from plants is at its lowest. Watering deeply provides a larger ‘reservoir’ of water in the soil and also encourages the development of deep root systems that are more drought resistant. About 10mm (sandy soils) to 30mm (loamy soils) of water should be applied to wet the soil to a suitable depth - Get to know your garden and its water needs.
Conditions within a garden can vary dramatically. There might be cool, shady areas or hot, dry areas; sections with well-drained soils or boggy soils; sloped or flat areas. Take advantage of this by choosing plants that are suited to the 'local' conditions or microclimates of your garden. - Understand the performance of your irrigation system or sprinklers
There is more to watering your plants than just turning on a tap or setting a timer. A well-designed irrigation system will apply water uniformly and at the correct precipitation rate. High watering rates can result in runoff rather than infiltrating the soil. Check the uniformity and application rate by using a number of catch-cans (pet food tins) spaced evenly between sprinkler heads. Measure depth of water in tins (in mm) after watering .For many soils, the precipitation rate should be less than 10mm per hour. If this is being exceeded, cycle your irrigation by operating for short periods with time for soaking allowed in between. Significant variation of water depths between the catch-cans can suggest poor efficiency. Consider changing sprinkler types and or spacing. The watering diameter of sprinklers should reach each other, or what is termed ‘head to head’ spacing. - Good maintenance keeps a dry garden in great condition.
Regularly check for pests and diseases, and keep your garden weed free. Ensure that your sprinkler system is operating efficiently to avoid wasting water. - Improve your soil.
In new garden beds, incorporate about 40mm of well-composted, fine organic matter in the top 200mm of the soil profile. This should improve the water-holding capacity of the soil. For established gardens, the regular application of mulch will also improve water-holding capacity by gradually increasing the organic content of the soil. #More detailed information on irrigation management and improving efficiency can be found in the Royal Botanic Gardens Irrigation Management Plan *Many drought-tolerant plant species have the potential to become environmental weeds in particular habitats and threaten our precious natural areas. Please check this with local horticultural experts, nursery or garden centre staff, and or consider local government information prior to planting.
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