Apart from making a garden bed look neat and finished, mulching provides a range of benefits.
Mulch Helps Provide Moisture Control
Living in south east Queensland, one of the most important aspects of mulching is moisture control.
A layer of mulch allows water to seap through into your garden beds. It then slows evaporation by providing a protective layer against the sun and heat.
Keeping the soil moist also helps when it comes time to water your garden. Moist soil will more readily accept water. If you’ve ever needed to add wetting agents to your garden, you’ll know what I mean. Water runs straight off a dry garden. It’s the same reason why watering a dry pot plant isn’t very effective. Or trying to mop up with a dry cloth doesn’t work. Things that are dry don’t readily accept water. Things that are damp do.
In summary, mulching helps keep your garden moist. And in doing so it also makes watering much more effecient and effective.
The heat of a south east Queensland sun will bake exposed soil. A layer of mulch provides cover for that soil, preventing it from becoming too hot. (It’ll do the same in Winter but that is less of a concern for us here in Qld.)
Plants stress in the heat just like you and I would if left to stand in the heat all day. Regulating temperature is therefore an important role of garden mulch.
The other reason we want to regulate temperature is related to our first advantage of mulch (above). Lowering soil temperatures will reduce the evaporation and help keep moisture in your soil.
Mulch Helps Protect Against Weeds
Mulch also provides a barrier against weeds. A well mulched garden is much less likely to have weeds popping up and taking hold. A mulched garden bed isn’t immune to weeds but it certainly makes the weed’s job harder.
Organic Matter Has A Range Of Benefits
We mostly use organic mulch in our gardens. This organic matter will decompose over time, adding rich organic compost to the garden soil.
Adding organic matter has so many advantages. It helps retain moisture, adds nutrients and grows a biome in your soil.
You may not realise it, but plants rely on a symbiotic relationship with fungi and microbes in the soil. Some help the uptake of nutrients while others break down decaying matter into nutrients your plants can use. The health of your garden is very dependent on the health of your soil. And this is where organic matter (mulch) can be so helpful to your garden.
Reducing Soil Compaction
Health soil, and therefore plants, depends on being able to allow for the movement of water, gases and roots through that soil. When compacted, the soil reduces those spaces and prevents your plants from thriving.
A lot of things contribute to soil compaction. Traffic on that soil (human or machine) will contribute. Excess tilling can contribute.
Mulch can help eliviate and protect. As stated above, mulch introduces organic matter into your soil. That helps prevent soil compaction. The mulch itself also is a protective layer on your garden.
Mulch Reduces Soil Erosion
If you’ve ever watched your soil float away when you’ve water, you’ll realise how much soil erosion can effect your garden. All that soil washing away is the nutrients that your garden needs.
A layer of mulch will help reduce erosion. Many of the factors mentioned above, such as keeping the soil moist and adding organic matter, will help prevent soil erosion. The most obvious though is the protective layer it provides between the soil and water from rain or watering.
And Mulch Looks Good
To me, a mulched garden looks finished. The layer of organic material helps delineate the plants, making the garden look neat and structural.
Nature seldom leaves soil bare. When it does we barren or desert areas where very few things flourish. It’s natural for us to see a mulched garden as a completed garden because that’s how nature herself works.