Using mulch liberally and regularly helps retain soil moisture. It does this by reducing evaporation, restricting weed growth and improving soil structure as it breaks down. Mulching also improves plant growth by providing insulation for plant roots.
Choose the right mulch
There are many different types of mulch to choose from. Organic mulch, such as sugar cane mulch or pine bark, will decompose over time and help improve your soil. Organic mulch should be reapplied frequently, preferably in autumn and spring, to replace the broken-down mulch.
Prepare for success
For the best result, prepare the soil by removing weeds, raking or digging the surface and watering the remaining plants. Place a layer of newspaper over the soil to deter weed growth, but make sure it’s not too thick as it will reduce air supply to the soil.
Be sure to keep the mulch about 6 to 7 centimetres clear of plant stems or they may rot.
The ideal thickness of the mulch layer depends on the particle size of the mulch material. If using large chunks, such as pine bark, a deeper layer (more than 5 centimetres) is needed. Mulch made of fine particles is more prone to compaction so it should be applied in a thinner layer.
Watch for nitrogen deficiency
As organic mulch decomposes it can draw nitrogen from the soil. Watch your plants for signs of nitrogen deficiency (usually indicated by yellowing of the lower leaves) and use a nitrogen-rich fertiliser if needed.