Using the Website


This program helps you calculate how much water your garden needs and will allow you to explore ways of watering your garden efficiently.

Calculate My Water Use
Divide your garden into areas or group of plants watered by a single method. For each area describe the plants, conditions (such as slope, exposure to sun and density) and watering method. The program will calculate the plant water demand, the water supply needed for healthy plants and a watering schedule for each month of the year. This can be viewed on a graph or printed.

Video: Calculate My Water Use

Explore Other Gardens
Use a Google style map or a list to explore gardens that other people have modelled to calculate water use.

Video: Saving, Sharing & Exploring Gardens

Read the latest news about SmartGardens, join discussions and meet other Smart Gardeners through Facebook, the world’s largest online community and sharing tool.

Calculate Water Use - Getting Started

The following information is required for the program to calculate water use:

  • Your garden’s postcode
  • Plant names (general types or specific species)
  • Watering system(s)
  • Mulch (if used)
  • Conditions (area and density of plants, slope and exposure)

Step by Step instructions

Before you begin, look around your garden and divide it into rough areas, where an ‘Area’ is a section of your garden that uses a common watering method. Use this single-page SmartGardenWatering Planner Form (213kB PDF) to help with this planning.

Now work with the program…

From the My Water Use tab, click the ‘Begin First Plant Area’ button and enter a name for your garden and its suburb.

Next, follow the sequence of 'post-it' note hints to:

1. Name and size your plant area
First click ‘Edit Area Name’ to give your first Plant Area a meaningful name and (importantly!) to enter its area.

2. Define your plants in ‘Plant Area 1’
Click the ‘Edit Plants’ link: the pop up area presents a ‘Browse Plants’ tab and also a more advanced ‘Search Plants’ tab. Choose plants for your Area. Closing the pop-up will show a graph of water demand for your garden.

3. Select a watering system
Click the ‘Edit water’ link to select a watering method. Make your selection. Closing the pop-up will add blue bars the your graph indicting the amount of water we recommend you apply to this Area each month.

4. Select mulch & other conditions
Click the ‘Edit Mulch’ link to choose your mulch – note the difference adding a mulch makes to your water demand graph! Also use the ‘Edit Conditions’ link to set conditions specific to your garden.

Understanding the graph
The graph shows the plant water demand (green bars) and supply (blue bars) needed for healthy plants for each month of the year. Usually there is a gap between demand and supply because an additional optimal-depth watering would take the water supplied past what is demanded.

Printing a watering report
Click the ‘Watering Report’ button to see a summary of your entire garden that can be saved as a PDF document and printed.

Finally, saving your garden
To register (so that your garden is saved online for later viewing and editing) simply click the ‘Join’ link at the top right of the screen and enter your details. (Fear not, your email address will not be passed on, and will not be used for purposes other than a possible rare contact informing you of important information relating to this software.)

Why not also click the "hidden" button (near top left) to change your garden's status to "visible" so that others can also see it?

What next?
Explore other links on the screen. For example, ‘Show Rain Tank’, ‘Rainfall Data’, the social networking links at the top right, and the ‘Community’ tab.

Water Graph - Demand (Green Bars) versus Supply (Blue Bars)

The 'demand' (green bars) show the calculated amount of water required for a plant. This takes into account rainfall and evaporation for the area, soils, mulch, garden conditions, etc. The 'supply' (blue bars) show the calculated amount of water needed to be supplied based on 10mm waterings.

The difference is essentially because the 'supply' is calculated in fixed volumes of 10mm waterings and where the final watering would take supply over demand, it is not applied. It is assumed that applying slightly less water than demand will save water whilst not unduly affecting the health of the plant.

Sizing and using a rainwater tank

Calculating the size of a rainwater tank
The volume (in litres) of a cylindrical tank is approximately height x diameter x diameter x 800 (all measures in metres).
The volume of a rectangular tank using length x breadth x height x 1000 (all measures in metres).
There are 1000 litres in a cubic metre.

Calculating the size of a catchment area (generally the roof) The area of square or rectangular shape is calculated by multiplying length by width.
All measurement should be in metres and measure the plan area, not the actual area of roofing material (This applies to sloping roofs).
Assuming that all the rain that falls on your roof can be trapped in a tank, 1 mm of rain falling on a square metre of roof delivers 1 litre of water. So, a 10 mm fall of rain on a 250 square metre roof would deliver 2,500 litres of water to a tank.

Rainwater tank – other use
The rainwater tank may also be used to supply water for the toilet, washing machine or some other household appliance. This generally represents a constant draw of water for each week that can be calculated and averaged. As an example the weekly water use for a 4 person household is calculated:

  • Modern dual flush toilet averaging about 18 litres per person, per day - 4 persons x 18 litres x 7 days = 504 Litres per week
  • Older toilet may use around 11 litres for a full flush and 54 litres per day - 4 persons x 54 litres x 7 days = 1,512 Litres per week.

A four or five star rated washing machine uses around 50 litres per load, so assuming 1 load per day, the weekly water use for a four person household is therefore:
4 persons x 50 litres x 7 days = 1,400 Litres per week.

Water level in the rainwater tank
The calculations for the estimated number of litres of water in the tank at the end of each week is based on average rainfall over the last 10 years and so the tank's actual water content may not be the same as in the prediction. It is assumed that only 90% of rainfall actualy flows into the tank.

As more areas are connected the water level in the tank will drop until the tank is empty for some of the months.
The graph estimates the water level in the tank assuming average rainfall for the region. The calculation is done week by week. But remember, if the tank is attached to any plant areas in the garden, then water might be going out as well as coming in. This means that any parts of the graph that sit along the zero axis don't necessarily mean that there is no water for the garden - it might be coming in and going out at about the same rate. This can be explored by turning all zones off using the check box(es) - this will show the amount of water that would be in the tank had it not been used.

Create/Edit garden name

The garden name should be meaningful to you without including detailed address information. Garden names are used to identify saved and shared gardens.

Garden Areas

Each 'area' is a physical space containing a group of plants that are watered from the same source. Ideally the plants in an area are similar in terms of their water use. In the case of mixed varieties of plants in a single area, the calculation will use the plant with the highest water need to calculate water demand for the area.

The area in square metres for common plant 'areas' can be calculated as follows:

  • Square or rectangular area = length x width
  • Triangular area = length x width divided by 2
  • Circular area = 0.785 x diameter of area x diameter of area

Explore other Gardens

The droplets on the map show how many smart gardens are located in that suburb or location. Click through to examine individual gardens, see what other gardeners have planted, how much water is used and whether a tank is used.
Other gardens can be marked as favourites and added to your list. A user may also nominate gardens using the like function in facebook.

Participate in the SmartGardenWatering community

Participate in the growing community of smart garden waterers by reading and sharing information. Share garden watering models with other gardeners, read the latest news, rate other gardens and participate in smart garden watering discussions.

Read SmartGardeningWatering news
Smart gardening news is found under the community area. It contains the latest updates from garden experts and developers for smart garden watering.

Show your Garden Model to Others
Every garden created is private by default and can only be seen by the owner. the owner can make a garden public so other gardeners can see it on a map when they explore. The only information made public is the suburb and garden name and content of the model. Email addresses and profile names are not shared.

Rate Other People’s gardens
Other gardens can be explored and rated using the Facebook ‘like’ facility. This allows a user to mark and share a garden with friends.

Participate in SmartGardenWatering Discussions
Participate in discussions, make comments and see the latest activity in the SmartGardenWatering community using Facebook. A SmartGardenWatering Facebook page has been established where ideas and information can be shared.

Manage your profile

Create my Profile
A profile allows you to save a garden and return to it later for editing or viewing. It also allows you to mark & remember other gardens as favourites.
Creating a profile requires minimal information and your location is not saved or shared with other gardeners in any greater detail than the postcode of the suburb in which the garden is located.

Why only Victoria?

This program was originally funded by the Smart Water Fund (financed by the main Melbourne metropolitan water suppliers) to cover the Melbourne/Geelong areas. Hence it originally had access only to Melbourne/Geelong soil, climate and plant data. Late in 2012 the University of Melbourne injected a small amount of extra funding to extend the coverage to regional Victoria - this new version was launched in early 2013.

We would love to expand to other areas of Australia, but this would depend on further funding and user demand.

Please use the feedback form to indicate where you would like to be able to use this program.