Mulch is an important part of a healthy garden. It helps retain moisture in the soil, keeps it at an even temperature and prevents the growth of weeds, which compete with your plants for water and nutrients.
What is mulch?
Mulch is any material used to cover the soil around your plants. The two types of mulches are organic and inorganic. Organic mulches are natural products such as straw, bark and leaves. They break down over time, adding to the nutrients in the soil. Inorganic mulches are gravel, pebbles, plastic and anything else unnatural. They don’t break down so won’t need to be topped up but add nothing to the condition of the soil.
Which mulch is best?
The best type of mulch is fairly coarse which allows for air circulation around plants and penetration of water into the soil. Finer mulches like lawn clippings are best put into the compost heap where they can break down and applied to the soil at a later date to improve it that way.
Types of mulch
Mulches such as sugarcane, pea straw, lucerne are good for vegetable gardens, around fruit trees and flowering plants. As they break down, they release nitrogen into the soil, which is great for general plant growth. These mulches are sold in bales so are easy to transport and distribute.
Woody mulches come in a range of different colours and can be used as a design feature around the garden. Darker mulch looks great in a native garden as it imitates how these plants appear in nature. Woody mulches have the advantage of not breaking down as quickly as straw-type mulches so you don’t have to top it up as often.
Succulents and cacti naturally grow in arid areas, so inorganic mulch like rocks and pebbles really suits them. It also makes these plants stand out so the garden is even more striking.
How much do I need?
Mulch is usually sold by cubic metre, which means you need to calculate the volume of the area you want to cover before buying. The depth of your mulch should be between 5 cm and 7 cm, depending on the type – less for inorganic varieties. To do this, simply measure the length and width of the areas (in metres) and multiply this figure by between 0.05 and 0.07m. If you are mulching a small area, you can also buy 60L bags instead of purchasing cubic metres – This can be more expensive, so be sure to calculate how much you’ll need first.
Laying mulch
There are a few tips to putting in mulch for the best results. Water well before applying mulch so you start with moist soil. Lay it a maximum of 5cm deep, and around 2-3cm for inorganic mulches. Keep it away from trunks of trees and stems of plants. Woody mulches remove nitrogen from the soil as they break down so occasionally fertilise to compensate.
Mulching vegie patches
When applying mulches to food-producing garden beds, use an organic mulch like pea straw sugarcane or lucerne. These organic varieties break down reasonably quickly and, as they do, add valuable nutrients to the soil, help improve soil structure and drainage, and encourage soi; microbial activity – great for plant health! They also give your veggie beds a beautiful, natural look. It is common to see fresh grass clippings used as mulch on veggie patches, however, it’s best to add them to the compost heap and let them break down before adding as compost to veggie patches for garden beds.
Mulching garden beds
Mulching is good practice but it also helps garden beds look their best. Consider applying a layer of a more attractive mulch – dark compost or fine bark look great – over garden beds, using a rake to help spread it evenly. If you can’t mulch the entire bed, get good coverage of the edges, sprinkle it in thinner layers as you move towards the back of the bed.
There are a variety of mulches you can choose from to cover garden beds, around shrubs, flowers and trees. If you are looking for a natural, low maintenance option, then go for wood chips or shredded bark. They decompose slowly and come in a variety of colours, textures and shapes, so you are bound to find an option to suit the look of your garden. If you prefer a mulch that needs very little maintenance you’re trying to recreate a certain theme, Inorganic mulches like pebbles or gravel can also work well. However, they don’t break down, so do not provide the soil with any nourishment.
Play areas
Mulching around play equipment for kids play areas will help soften their fall in case of any accidents. Look for material specially designed for playgrounds, like soft fall or fine-grade pine bark mulch. These are the finest, softest mulches you will find and feel slightly spongy.
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