Mulch and fertiliser
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. If you only have one type (such as grass clippings) it will still work. If you are only using grass clippings, use a thin layer at a time. Keep it fluffed up to allow rainwater to penetrate. Do not add your grass clippings to the base of street trees. They can heat up and kill the tree's feeder roots at the surface.
- 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.
- As the mulch layer breaks down into the soil, add more mulch to the top layer.
Benefits of mulch
- suppress weeds
- act as a natural slow-release fertiliser
- provide a home for plant-friendly insects and micro-organisms
- retain 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.
For more information about compost and organic recycling, attend one of Council's free compost and worm farm workshops.