Gardening tips

How much does it cost to water my garden?

Running your garden hose for an hour uses up to 400 litres and costs around $1.39, depending on your water pressure.

This cost is made up of both water and wastewater charges, but we make allowances for outdoor water use. This applies year-round, even during the cooler months when you are unlikely to be in the garden or cooling off the kids with the hose.

Put simply, for every 100 litres of water that enter your property, we only charge you for 78.5 litres of wastewater. This allows 21.5 litres for outdoor activities such as washing your car and watering your garden.

Although most domestic properties are charged at 78.5 per cent for wastewater, this does vary. Check page 2 of your bill: Consumption details.

Watering the garden

The amount of water you need to keep your garden going through summer depends on several factors: 

  • Soil type: Clay soils absorb water slowly but are prone to compaction. Sandy soils do not retain water well but are easier to work.

  • Plant variety: Some plants require a lot of water to stay healthy and looking good. Visit your garden centre for more information on waterwise plants.

  • Organic content of the soil: The more compost and organic content in the soil, the more it will retain moisture and the less watering it will need.

  • Mulched versus naked soil: A few centimetres of mulch on the soil increases water penetration, improves soil fertility and structure, reduces weeds and protects soil against evaporation and erosion.

  • Drainage

  • Slope, shade, wind, amount and frequency of rain.

Gardening choices

  • Group plants with similar watering needs, to ensure they all receive the correct amount of water.

  • Place mulch around your plants to minimise loss of water through evaporation. You can use wheat or pea-straw, bark or grass clippings. Don’t place mulch too close to your plants’ stems as it can cause them to rot.

  • Weed your garden regularly. Weeds compete with plants for the available water. 

  • Even at the height of summer, only water your garden once every three to five days that pass without rain. It is better to water deeply and infrequently rather than lightly sprinkling every day. By watering every day, you promote a weak and superficial root system that is prone to drying out.

  • Check to see if the soil is dry before watering your garden. It’s easy to over-water!

  • Water your plants in the early morning or evening to minimise evaporation.

  • Water the base of your plants rather than the leaves so that the water can reach the roots. An easy way to water the roots and reduce evaporation is to use a drip irrigation system.

  • Reuse water where possible. Tip soapy water from the house or dirty water from your fish tank over your plants – but remember that some plants cannot deal with water softeners and harsh detergents, and avoid the vegetable patch.

  • Use a watering can or a hose with a hand-held trigger to minimise waste, and direct water only where it’s needed. If you need to use a sprinkler, also use a timer. If your sprinkler is spraying water on the driveway or paths, turn it down or move it. Some sprinklers use as much water in an hour as a family of four uses in a day.

Plants that do well in dry conditions

  • salvia

  • succulent

  • clivia

  • libertia

  • arthropodium


  • Look for a drought-resistant lawn seed mix when laying a new lawn such as perennial ryegrass and fescues.

  • Some lawn grass mixtures can be left to dry out and go yellow in summer. They will recover in autumn. Avoid cutting them short before you stop watering them.