Mad About Berries

Things to Know About Cedar Mulch

If you want to put mulch down in your garden, you’re probably weighing up the pros and cons of the many different kinds of mulch and wondering which one to opt for. Cedar mulch has some major benefits, but is it right for you? Let’s find out!

Cedar mulch is great for repelling unwanted insects, and it provides a low-maintenance area of cover. It is good at trapping moisture and resisting temperature changes, and it can prevent weeds from growing in places where it has been laid. It sometimes depletes the amount of nitrogen in the soil, however, and some people dislike the smell.

Published: October 19, 2022.

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We’ll use this article to explore cedar mulch and its benefits and drawbacks so you can decide whether this is a good material to use in your garden.

1) Cedar Mulch Repels Insects

One of the biggest benefits of cedar mulch is that it can help to repel insects. This makes it popular in parts of the world where insect damage is a big problem. It provides a natural form of pest control because a lot of insects seriously dislike the smell of this mulch.

All sorts of insects are affected by the smell, including things like cockroaches, ants, termites, moths, and more. This is because it contains an oil called thujone, which these insects hate. Laying cedar mulch around your home might therefore discourage ants and termites from taking up residence nearby or even in the home.

However, there is a significant drawback to this. The oil does not only affect pests: it is also a major deterrent to things like ladybugs and lacewings, which are beneficial predatory insects that you want in your garden. You will be reducing the biodiversity in the garden, and this can upset the natural balance.

You should therefore weigh up whether to add cedar mulch in a particular location carefully. If you want to repel all insects from that area, it might be beneficial, but otherwise, be cautious about laying it.

2) It’s Low Maintenance

You don’t want mulch in your garden that needs constant attention and work – the point of laying mulch is often to reduce the amount of work you need to do in any particular area.

Fortunately, cedar mulch is not high maintenance. You can lay it and forget about it, and it will mostly take care of itself. It should take several years to decompose, and it can last a lot longer than other kinds of mulches because it is mold and bacteria-resistant.

That means it is often cheaper in the long term, and it requires less work. Once laid, it will stay in place year after year and only gradually break down. However, this is balanced by the fact that it is often one of the more expensive mulches, so you will be paying more upfront for it.

You will therefore have to make a judgment of work vs. cost and decide which you value more. Cheaper mulches will need more frequent replacement and more work.

3) It Traps Moisture

Mulches are ideal if you want to lock moisture into your soil, and fortunately, cedar mulch does this particularly well. It will create a dense layer on top of the soft soil, allowing water to trickle down but making it harder for it to evaporate again when the weather changes.

However, you do need to make sure you check your mulch from time to time. Sometimes, mulches compact too much, and this can prevent water from running into the soil below. That means you will have to spend some time “fluffing” up the mulch and moving it around so that pockets for air and moisture are created.

Be aware that if your mulch gets very dry in hot weather, it might struggle to reabsorb moisture, and this prevents the soil from getting wet. Thoroughly soaking it should help to solve this.

4) It Prevents Weed Growth

Cedar mulch is a dense option that is effective when it comes to stopping weeds from growing. This is one of the major reasons that people use mulch, so if you need to prevent growth in a certain part of your garden, cedar mulch should work well.

You need to make sure that you don’t add such a dense layer you smother existing plants, however.

5) It Can Cause Nitrogen Depletion

This is a common problem with mulches, particularly if you are using them around existing plants. It is sometimes confusing because cedar mulch contains some nitrogen, and as it decomposes, this will be released into the soil. However, in the meantime, it can lower the amount of nitrogen available.

This happens because the decomposition process requires nitrogen. The microorganisms responsible for breaking up the cedar wood and making it into compost will pull nitrogen out of the surrounding soil. This can cause a temporary nitrogen deficiency in the surrounding soil.

This usually only affects plants with shallow root networks that are very close to the mulched area. Deeper-rooted plants will normally be fine, as they can simply draw nitrogen up from lower down. However, it may affect young or poorly established plants, so be aware of this.

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6) It Has A Strong Smell

One of the reasons that cedar mulch is good at repelling insects is that it has a strong odor. As we mentioned earlier, that can be both a benefit and a drawback, but it does mean you also need to think about whether you like the smell or not.

This may not matter if you use the mulch in your backyard and you rarely go into that area, but if it’s on flowerbeds where you will frequently be sitting or working, you need to think about the scent.

Many people find the smell of cedar mulch pleasant, but it is quite strong, and some people dislike it. If you find it is not to your tastes, you might prefer to choose another kind of mulch, at least for the high foot traffic areas of your backyard.

7) It Can Make Your Soil More Acidic

One of the drawbacks of cedar mulch is that it can make your soil more acidic as it decomposes. This will not often be a problem as the difference is minor, but if your soil is already low on the pH scale, there is a chance that it could make it inhospitable to the plants growing there.

Adding a lot of cedar mulch to acidic soil will potentially cause problems, especially in the long term. You might wish to mix in a neutral mulch alongside if you are concerned about this, or utilize soil testing kits to check the soil’s pH value before you start.

8) It Is Attractive

One of the top reasons for mulching is that it makes your garden look neater. It results in far fewer weeds and creates a “put together” appearance that many people like. Spreading mulch in between your plants can stop others from growing, but if the mulch itself looks a mess, this doesn’t help much.

However, cedar mulch has an attractive and neat appearance, so it will make your garden look tidier. Because it lasts well, this is a sustainable solution for keeping weeds out of your flowerbeds and preventing plant growth in spots you want to keep clear.

9) Cedar Mulch Is A Good Insulator

Another major reason for laying mulch is to protect your plants from being damaged by extreme heat or extreme cold. Mulch adds a layer of protection on top of the soil that minimizes temperature changes – but some mulches do this more effectively than others.

Because cedar mulch is dense, it’s an excellent insulator. It provides temperature regulation that reduces the fluctuations that are often so damaging to plants. Even if the temperatures are very low, it can prevent the soil from freezing hard, protecting the roots.

It will also stop your plants from being deceived by warm days in very early spring. If the sun is hot but the nights are still cold, your plants might be tricked during the day into starting to sprout. When the temperatures then drop again, these sprouts will freeze, wasting the plant’s energy and causing stress.

The cedar mulch will prevent this from happening by keeping the plant’s roots cool even in the spring sunlight and only allowing gradual temperature changes. This can reduce the risk of your plants being killed by spring frosts.

Similarly, cedar mulch will help your plants in the summer by ensuring that the ground does not get baked by the sun. This helps to trap moisture and keeps the temperatures down, meaning your plants should better withstand heat waves.

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Cedar mulch can be very beneficial to your garden. It regulates temperatures, traps moisture, and suppresses weeds.

It can also prevent problematic insects from moving in, although it will deter beneficial ones as well – so place it with care. If you have very acidic soil, cedar mulch is not an ideal choice, so consider other mulches instead.

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