Mulch and fertiliser | Brisbane City Council

Mulch and fertiliser

Learn how to make your own mulch from garden waste such as leaves, grass clippings and prunings to help improve the quality of your soil and the health of your garden. Use this page to also find tips on the responsible use of fertilisers in your garden to give it the best chance to thrive.


Mulch is garden waste such as leaves, grass clippings and prunings. Some weeds can also be used for mulch, but make sure they don’t have seeds.

When you place mulch around plants in your garden, the mulch will break down on the surface of the soil. The nutrients in the mulch are absorbed by the soil to feed the plants.

The best mulch uses a mixture of garden materials, but if you only have one type (such as grass clippings) it will still work.

  1. Place garden waste in a 10 centimetre deep layer on top of the soil in and around your plants. Take care not to allow the mulch to touch plant stems.
  2. As the mulch layer breaks down into the soil, add more mulch to the top layer.

Benefits of mulch

Mulch can:

  • suppress weeds
  • act as a natural slow-release fertiliser
  • provide a home for plant-friendly insects and micro-organisms
  • retains up to 70% more moisture than unmulched soil


Over-use of fertilisers can cause algal blooms and increase weed growth in our waterways. This disturbs the ecological balance for the animals and plants that live there. Native plants have evolved in nutrient-poor soils and do not need fertilisers.

If you do use fertilisers:

  • question if you actually need them
  • check their composition (i.e. organic or artificial)
  • follow the manufacturer’s instructions carefully
  • don’t fertilise just before or during rain to minimise wasteful run-off
  • never put fertilisers or pesticides in or near creeks or stormwater drains
  • never empty fertilisers or pesticides into creeks or stormwater drains.

More information

If you'd like to learn more about compost and organic recycling, attend one of our free compost and worm farm workshops.

04 October 2017