What You Need to Know About Black Mulch: Types & Benefits

During the long, hot summer in Australia, mulch is an essential addition to a garden. It helps to slow down the evaporation of water from the soil, keeping a consistent level of moisture. As such, it reduces the need for watering during hot waves. And black mulch is the most common choice Australian homeowners make.

Through shredded bark might be the first thing that comes to mind when you picture black mulch, did you know you can use other materials too? This can be anything from plastic to lava rock. Depending on your garden and what you are planting, one of these black choices may be the most suitable option for you.

Wood Chips

Usually, good quality black mulch is composed of wood chips that are dyed black using carbon black die. This type of die is also often used in the production of ink or paint. The base for this dye is considered natural, non-toxic and safe for handling. Not only is the contrast of the black mulch with green leaves and bright flowers amazing, but black mulch also absorbs heat on warm, sunny days as well. During a hot summer, the excess heat can burn delicate plants. On the other hand, during a cooler climate, mulch protects the soil from freezing and can keep heat-loving plants happy.

Besides protecting the soil from the weather, black mulch made of wood chips can also be used as a decorative elements for the landscape. For instance, if you have a bare, empty patch in your garden that sticks out like a sore thumb, you can cover it up with the help of wood chip mulch.

black mulch for garden with decorative pink flowers green grass and stones

Source: rubbermulch.com

Plastic Sheeting

While not many see plastic sheeting as a mulch, gardeners growing strawberries and other tender fruits and vegetables, often use black plastic under and around the plants. Black plastic has the ability to absorb heat on sunny days, elevating the temperature of the soil while keeping the moisture levels even. Black plastic also prevents weeds from sprouting by preventing the sunlight from reaching the seeds.

Lava Rock

Used both in commercial and home applications, black lava rock is often applied over a weed barrier cloth. Once installed, it tends to stay in place despite heavy winds or water runoff. Black lava rock has the ability to retain the sun’s heat, creating a warm microclimate when placed next to a sunny, south-facing wall.

Rubber Mulch

The flexible and impact-absorbent characteristic of black rubber mulch makes it a common choice for playground areas, under outdoor athletic equipment such as pull-up bars and in walkways. Thanks to its cushioning ability, it’s a safe cover for creating an active families play area. Made of recycled shredded tires, rubber mulch is considered nontoxic and safe for use in the garden. Still, most gardeners prefer to use biodegradable mulch around their plants.

rubber bark mulch for garden

Source: heffcogroup.com

Benefits of Mulch

There is a number of benefits to adding mulch in your garden. In the summer, mulch helps the soil retain moisture better so you don’t have to water as often. Soil also tend sto dry faster and become hard in the hot sun. Mulch helps protect the soil from direct sunlight, keeping your plants happy.

In the winter, the soil under the mulch will stay warmer then unprotected soil. This helps protect the plant roots from the cycle of freezing and thawing. Other benefits of mulching include:

  • Reduces soil erosion and minimises soil compaction;
  • Prevents the soil surface from crusting. That is because water moves more readily into soil covered with mulch instead of running off;
  • Prevents the soil from splashing onto leaves, which reduces plant diseases;
  • Enhances the structure of clay soils and the moisture-holding capacity of sandy soils;
  • If organic, the mulch can increase soil fertility and may make micronutrients already in the soil more available;
  • Due to fewer weeds, more constant moisture and soil temperature, mulch helps improve plant health and growth;
  • Makes garden beautiful and attractive, giving a uniform appearance and rhythm to garden design.
applying mulch in the garden

Source: landscapemulch.com

How to Apply Mulch

If you need to replenish your mulch in the fall, do it by late summer or early autumn, By that time, the soil may not be too cold and plants may be able to continue to grow. Avoid applying mulch in mid-to-late autumn as new growth may not harden off and can be damaged by winter cold. Furthermore, mulch in the fall might keep the soul wet which can lead to root rot and plant death.

Once you’ve had several freezes and the soil has cooled, you can apply winter mulch to protect any tender plants or new plants that may not make it through the winter. Keep in mind that plants correctly selected for hardiness do not mulch in the winter. Winter mulch should be deeper. Apply 7 to 10 centimetres while being careful to keep the mulch away from the crown of plants and not piled much against trunks of trees and shrubs. When spring arrives. make sure to reduce the mulch to a depth of 5 to 7 centimetres.

If you have a large garden and are mulching it for the first time, you might want to look into getting a delivery from a bulk supplier. It’ll be less expensive than buying a ton of bags of mulch from your local garden centre.