Mulch

Before mulching, remove any grass, weeds and dead plants from the bed.Put in any new plants before applying your mulch layer.

Mulch can be applied at any time, but is best applied in mid spring or early summer.How you are going to water the plant needs to be considered before the mulch is laid. Drip soaker hoses placed below the mulch work more effectively. Water applied above the mulch may not always get down to the soil. After rainfall or watering dig down to see how the water progressed through the mulch. The soil can still be dry even after heavy rainfall - an all too common problem.Do not pile mulch up against the stems and trunks of plants. Piling mulch against plant stems can lead to trunk rot and plant death.

Use inorganic mulches for native plants growing naturally in low nutrient soils. Before selecting what type of mulch to use take into consideration where the native plants you are using originate from - eg. for inland plants from drier areas, a mulch of gravel may be the best option as damp organic mulch often leads to fungal problems with these plants. On the other hand, for rainforest plants, deep green organic mulch would be a better option.

Application

In temperate climates, the effect of mulch is dependent upon the time of year at which it is applied as it tends to slow changes in soil temperature and moisture content. Mulch, when applied to the soil in late winter/early spring, will slow the warming of the soil by acting as an insulator, and will hold in moisture by preventing evaporation. Mulch, when applied at the time of peak soil temperatures in mid-summer, will maintain high soil temperatures further into the autumn. The effect of mulch upon soil moisture content in mid-summer is complex however. Mulch prevents sunlight from reaching the soil surface, thus reducing evaporation. However, mulch can absorb much of the rainfall provided during light rainfall, which will later quickly evaporate when exposed to sunlight, thus preventing absorption into the soil, whilst heavy rainfall is able to saturate the mulch layer, and reach the soil below.

In order to maximise the benefits of mulch, whilst minimising its negative influences, it is often applied in late spring/early summer when soil temperatures have risen sufficiently, but soil moisture content is still relatively high.[2] Furthermore, at this point in the growing season, plants should be well enough established to be able to cope with the increase in the numbers of slugs and snails owing to the habitat provided for them by the mulch.