Adjust your irrigation for the seasons

Wet Season

There is really only one irrigation rule of thumb in the Wet season.Turn it off when it rains! However, keep an eye on your garden and only water it if it looks really thirsty.

Between January and March you can almost 'hear' your garden grow, so why not let the rain do the watering for you for a couple of months and switch your irrigation system to 'off', just keeping an eye on your plants and giving them a drink if there is a break in the rain.  .

You could save up to $200 on your water bill. Note - This saving is based on a flow rate of 25L/min (average irrigation systems). On a controller that has four zones each set to run 20 minutes per day, you would save 120,000L or $218 in that period

Other things to consider for a healthy garden (and wallet) during the wet season:

  • Some homeowners tell us that they are worried about turning off the irrigation for a few months in the wet season in case it deletes their system's water program. Don't worry - your irrigation controller will keep it all there for you for when you are ready to turn it back on and if you have any problems you could book in a Garden Tune Up at the start of the Dry and an expert irrigator can schedule your irrigation to be water efficient and specific to your garden.

  • Not sure how to turn off your irrigation system for the wet season? Most of the time it's just a matter of pressing the OFF button, or you can switch it off at the wall. But if you have lost the manual for your irrigation controller and don't feel confident without it, you may find it here or visit the Darwin Watering Planner.

  • Maintenance - Even when your irrigation system is off for the Wet season, it is a good idea to check it regularly so it is well maintained and ready for use in the Dry season. Check for split irrigation pipes and hoses or missing drippers. You might also like to run the system for a few minutes each week to keep ants from blocking the system.

  • In the heat and humidity weeds and pests thrive. Keep an eye out for them during the wet so you are not overrun by the Dry!

  • The end of the Wet Season is a good time to get veggie beds ready for planting.


Most Top End soils struggle to hold water and food for plants. Top End soils are generally sandy or clay loams and have a low water holding capacity with high percolation rates. This means they don't retain water and nutrients very well which can affect the health of plants. The secret to creating a beautiful, water efficient garden in the Top End is getting the condition of your soil right, so it is full of healthy micro-organisms to help feed and maintain the vigor of your plants.

Three easy ways of improving your soil condition are:

  1. Mulch
  2. Organic fertilisers
  3. Wetting agents


  • Mulch, mulch, mulch! It is not only good for your plant's health, but will increase moisture retention within the soil.
  • Mulch will also help keep plant roots cool, assist in suppressing weeds, add biomass to soil structure and can assist with drainage.
  • Rich organic mulches are vital for plant nutrients, maintaining soil quality and to prevent erosion.
  • Remember, mulch pushed against tree trunks can encourage rotting during the wet, so make sure there is space around the trunk to allow for airflow.

Dry Season 

Great gardens need great irrigation schedules. Irrigation scheduling is mainly about two things:

  • Wetting the right depth of soil
  • Watering at the right frequency

More water doesn’t mean a better garden. If you water too frequently your plants will be shallow rooted and nutrients will be washed away. Even if you put lots of water on every day, roots will not grow deep and will only be able to access a small amount of groundwater and nutrients.

Different plant types need different amounts of water at different intervals. If you're planning your garden, or putting in new plants, think about grouping your plants according to how much water they need.  This is called hydrozoning.  You can then set up you irrigation into zones so that you can water each group of plants just the right amount according to their needs.  And easy way to group plants is:

  • Group 1:  Fruit trees and exotics
  • Group 2:  Natives
  • Group 3:  Lawn

When setting your watering times, an easy rule of thumb in the Dry season is the 3, 2, 1 Rule:


We recommend you take advantage of our free Garden Tune Up  where one of our registered irrigators will help you schedule your irrigation controller so that you have a water efficient garden that will thrive!