Mulching
Mulching your garden can reduce water loss from evaporation by 70%.
Traditionally, about half of all household water in Queensland is used in the yard. Gardens make up a large part of this water use.
Mulch is garden waste, such as lawn and plant clippings, leaves and shredded garden waste like bark and wood chips. Mulch prevents moisture loss through evaporation. It does this by reducing soil temperature, returning nutrients to the soil, inhibiting weed growth and keeping a plant’s root ball cool.
Pebbles, stepping stones and decorative gravels are now also being used as mulches.
You can make your own mulch or buy it from landscaping suppliers.
How to mulch
The first thing to do is determine how much mulch is needed on your garden. You do this by calculating the surface area in square metres, and then dividing by ten. For example, if your garden is two metres wide and 10 metres long, you would need two cubic metres of mulch – (10x2)/10=2.
Mulch should be applied so that it is no more than 10 centimetres deep.
It is best to use organic mulch, as it breaks down and releases nutrients to the soil. Examples of organic mulch include leaf litter, grass clippings, lucerne hay, compost, pine bark and pea straw.
You should only really consider using inorganic mulches, like rocks and pebbles, on plants like cacti that don’t require the extra nutrients of decomposing organic mulch.
Here are some things to consider when applying mulch.
- Before mulching, remove any grass, weeds and dead plants from the bed.
- Put in any new plants before applying your mulch layer.
- If installing an irrigation system, such as a drip system, do so before mulching.
- Mulch to a depth of 7.5-10cm deep.
- Mulch can be applied at any time, but is best applied in mid-spring or early summer.
- Do not pile mulch up against the stems and trunks of plants. Piling mulch against stems can lead to trunk rot.
- While mulch helps to retain soil moisture, mulched gardens still need watering (water restrictions permitting).
- Top up the mulch regularly to maintain desired thickness.
