As we head into summer again, now is the perfect time to think about garden mulch! Mulch will protect your plants, improve soil and encourage growth in your garden. Bare, exposed soil loses water rapidly through evaporation, and the hotter the weather, the faster the moisture disappears. So by insulating the soil surface with a layer of mulch, you’ll be conserving that moisture for the plant roots to use.
As Sophie Thomson (from ‘Gardening Australia’) has pointed out – “There are four important reasons to mulch. The first, and probably the most important, is for water conservation. Mulch stops the top of the soil drying out, keeps the soil moist, and can reduce watering by about 60 per cent. Mulching also prevents weeds and weed seed germination, which compete with plants for moisture and nutrients. Mulching also keeps the soil temperature constant, and using an organic mulch means you’re adding extra organic matter to the soil. “
As part of our landscaping services, Fence & Garden provide advice on the best types of mulch for your garden and will also supply, deliver and spread the mulch out for you.
Depending on the types of mulch you use, it needs to be topped up on a semi regular basis – something that many people simply forget to do.
There is a range of materials you can use as garden mulches, but they fall into two main camps – organic and inorganic.
Organic mulches are derived from plant-based materials, such as straw, shredded timber and bark. They break down over time which improves the soil’s structure and water-holding capacity. It also means that you need to top them up periodically with a fresh layer to maintain good coverage.
Straw Mulch: Great for vegetable gardens. It decomposes quickly and improves the soil as it decays.
Sugar Cane Mulch: Made from dried sugar cane leaves. It provides an attractive finish in garden beds that also encourages helpful soil organisms.
Pine Bark Mulch: Great for garden beds and pots. It’s dark natural colour blends in with the soil and looks great in any garden.
Coir Mulch: Fibre from the outer husk of coconuts. A more decorative mulch, you can get it in concentrated blocks, which quickly expand when you add water.
Hardwood Mulch: Great for suppressing weeds. It looks good and takes a while to decompose so you don’t have to replace it as often.
Lucerne Mulch: Gives your soil extra nitrogen as it breaks down. It’s ideal for roses, flowers, vegetables and fruit trees.
Woodchip Mulch: A great mulch and also makes an attractive feature in your garden.
Synthetic mulches are the best soil insulators because they don’t break down. They keep soil warmer for longer but don’t provide the same benefits as organic mulches as they don’t decompose and add nutrients to the soil.
Gravel / Pebbles: Permanent and best used for foundation plants. They make an appealing design feature that you can enjoy year after year.
Black Plastic / Weedmat: Most effective as weed control. It can break down in sunlight so it’s best to bury the plastic under your soil so that it lasts longer.
Landscape Fabrics: Similar to plastic but let air and water through more effectively. For best results, add another 6-8cm of organic mulch over the top.
How Deep should you Mulch Layer be?
If your mulch layer is too shallow, it won’t do its job. If it’s too thick, water may not be able to get through to the soil easily. As a general rule, spread a covering 2–6cm thick, using the higher level for coarse mulches such as chunky barks and wood waste products. Keep finer mulches like shredded straw to about 2–3cm, as thicker layers can pack down and make it hard for water to penetrate to the soil.
You might not be aware that Sunshine Coast Council also offers free mulch to residents at Buderim and Caloundra Resource Recovery Centres. You can check out what’s available at the council website.