Pros and Cons of Eucalyptus Mulch | A Simple Guide

Mulch helps to retain moisture, suppress weeds, and regulate soil temperature. Eucalyptus mulch is made from the leaves and bark of the eucalyptus tree. It is a popular choice for gardeners because it is long-lasting, attractive, and has a pleasant smell.

The pros of eucalyptus mulch its ability to help retain moisture in the soil and suppress weeds. The cons of eucalyptus mulch include the fact it contains some chemicals which can slow other plant growth and can be harmful if ingested by pets.

This article will explore the pros and cons of using eucalyptus mulch at home and some easy tips to use it right.

Pros of Eucalyptus Mulch

Here are some of the advantages of using eucalyptus mulch in your garden:

Improves Soil Health

Eucalyptus mulch is a natural source of nutrients that can help improve soil health. As it decomposes, it releases essential minerals and nutrients into the soil, which can benefit plant growth. Additionally, eucalyptus mulch can help regulate soil pH levels, which is important for optimal plant health.

Repels Pests

One of the most significant benefits of eucalyptus mulch is that it repels pests. Eucalyptus contains natural oils that are toxic to many insects or just the smell will keep them away.

By using eucalyptus mulch in your garden, you can reduce the need for harmful chemical pesticides. It is a natural pest repeller and a great option for putting around trees and shrubs.

Conserves Soil Moisture

Eucalyptus mulch is an excellent choice for gardeners who want to conserve soil moisture. It acts as a natural barrier, preventing water from evaporating from the soil. This can be especially helpful in hot, dry climates where water conservation is a concern.

Cons of Eucalyptus Mulch

While eucalyptus mulch has several benefits, it also has some drawbacks that you should consider before using it in your garden. In this section, we will discuss some of the drawbacks of eucalyptus mulch.

Allelopathic Properties

One of the primary concerns with eucalyptus mulch is its allelopathic properties. Allelopathy is the ability of a plant to produce chemicals that can inhibit the growth of other plants.

Eucalyptus trees contain high levels of essential oils that can be toxic to some plants. When eucalyptus mulch is used around susceptible plants, it can inhibit their growth or even kill them. Therefore, it is essential to use eucalyptus mulch carefully and avoid using it around sensitive plants.

Plants sensitive to eucalyptus mulch include:

  1. Vegetable Plants: Some vegetables, such as tomatoes, peppers, and potatoes, may be sensitive to eucalyptus mulch.
  2. Herbs: Herbs like basil, rosemary, and sage may be affected by the allelopathic properties of eucalyptus.
  3. Citrus Trees: Citrus trees can be sensitive to eucalyptus mulch, so it’s advisable to avoid using it around them.
  4. Lettuce and Spinach: Leafy greens like lettuce and spinach may not thrive when mulched with eucalyptus.

Decomposition Rate

Eucalyptus mulch has a slower decomposition rate than other types of mulch. It can take from 8-12 months to break down completely.

This makes it a great option for using around established trees and garden beds but not great for areas where you will be replacing the plants often or want to improve the soil with broken down mulch.

I like to use eucalyptus mulch that is finer, broken down into pieces that are a mix of leaves, branches and stems. This will help it to break down faster into the soil.


Eucalyptus mulch is generally more expensive than other types of mulch. If you are on a tight budget, there are other types of mulch that may be more cost-effective.

In Australia eucalyptus mulch is fairly common but is not usually as cheap as a regular garden mulch or pine bark mulch. Check out the prices at your local garden center to see what works for you.

Environmental Impact

One of the most significant advantages of eucalyptus mulch is its environmental impact. Here are some of the key factors to consider:


Eucalyptus tree trimmings can be reused and turned into mulch. This saves them going to landfill and releasing harmful greenhouse gases as they break down. Many arborists will mulch eucalyptus trimmings on site and will give it back to local councils or garden centres to re-sell.

Tips for Using Eucalyptus Mulch at Home

When it comes to applying eucalyptus mulch to your garden, there are a few best practices and common mistakes to keep in mind.

Prepare the area

Before applying the eucalyptus mulch, make sure the area is free of debris and weeds. This will ensure good contact with the soil and help the mulch to do its job effectively. Weeds will always find their way to grow through if you leave them there before mulching.

Apply a thick layer

For best results, apply a layer of eucalyptus mulch that is 2-3 inches thick. This will help to prevent weed growth and regulate soil temperature.

Water the area

Water the area thoroughly after applying the mulch. This will help the mulch to settle in and stay in place if it gets windy. The mulch will start to break down over time and nutrients will start to be released into the soil.

Reapply every 6-12 months

Over time, the eucalyptus mulch will break down and decompose. Top up the mulch every 6-12 months to keep it 2-3 inches thick. This will keep the weeds down and the soil moisture in.

Common Mistakes when Applying Eucalyptus Mulch

  1. Applying too thin of a layer: If you apply a layer of eucalyptus mulch that is too thin, it may not be effective at preventing weed growth or regulating soil temperature. Make sure to apply a layer that is at least 2-3 inches thick.
  2. Applying too close to the base of plants: When applying eucalyptus mulch, make sure to keep it at least a few inches away from the base of plants. If the mulch is too close, it can trap moisture and cause the plant to rot.
  3. Not checking for pests: Eucalyptus mulch can attract pests such as termites and ants. Make sure to check for any signs of pests before applying the mulch. If you do notice pests, consider using a different type of mulch or treating the area with an insecticide.
  4. Avoid adding it to vegetable gardens: It is best to use a lighter mulch like straw instead of eucalyptus mulch around vegetable gardens. That way it will break down each season and you can dig it in.

Comparison of Eucalyptus Mulch with Other Mulches

When it comes to choosing the right mulch for your garden, there are several options available. In this section, we will compare eucalyptus mulch with other popular mulches to help you make an informed decision.

Eucalyptus vs. Organic Mulches

Organic mulches such as wood chips, bark, and straw are popular choices among gardeners. They are made from natural materials and are beneficial to the soil as they decompose over time. However, they also have some drawbacks.

One of the main advantages of eucalyptus mulch over organic mulches is that it is highly resistant to decay. This means that it can last longer than other organic mulches, which can save you time and money in the long run. Additionally, eucalyptus mulch has a pleasant smell that can help to repel insects and pests.

On the other hand, organic mulches can be more affordable and readily available than eucalyptus mulch. They also provide more nutrients to the soil as they break down. However, they may need to be replaced more often.

Eucalyptus vs. Inorganic Mulches

Inorganic mulches such as plastic and rubber are becoming increasingly popular due to their durability and low maintenance. They are also effective at suppressing weeds and retaining moisture. However, they also have some drawbacks.

One of the main advantages of eucalyptus mulch over inorganic mulches is that it is biodegradable and environmentally friendly. It does not release harmful chemicals into the soil and is safe for plants and wildlife. Additionally, eucalyptus mulch can help to improve soil structure and aeration.

Inorganic mulches can be more expensive than eucalyptus mulch and may not be as aesthetically pleasing. They can also trap heat and cause soil to become too warm, which can be harmful to plants.

Overall, choosing the right mulch depends on your specific needs and preferences. Eucalyptus mulch can be a great option for those looking for a long-lasting, environmentally friendly mulch with a pleasant aroma. However, it may not be the best choice for those on a tight budget or looking for a mulch that provides more nutrients to the soil.

Frequently Asked Questions

What are the benefits of using eucalyptus mulch in gardens?

Eucalyptus mulch has several benefits for gardens. It can help to retain moisture in the soil, which reduces the need for frequent watering. Additionally, eucalyptus mulch can help to control soil erosion and protect plants from damage caused by insects. It also has an attractive, natural appearance that can enhance the overall look of your garden.

Can eucalyptus mulch help in repelling insects and pests?

Yes, eucalyptus mulch can help to repel insects and pests. The natural oils found in eucalyptus leaves and bark can deter insects such as ants, termites, and cockroaches. This can help to protect your plants from damage and reduce the need for harmful pesticides.

Are there any risks associated with using eucalyptus mulch around pets?

Yes, there are risks associated with using eucalyptus mulch around pets. The essential oils in eucalyptus mulch can be toxic to pets if ingested. This is similar to cocoa shell mulch, which can also be harmful to pets. It’s important to keep pets away from eucalyptus mulch and monitor them closely when they are in the garden.

How does eucalyptus mulch compare to cypress mulch in terms of effectiveness?

Eucalyptus mulch and cypress mulch are both effective types of mulch for gardens. Eucalyptus mulch is more absorbent than cypress mulch, which means it can retain moisture better and reduce the need for frequent watering. Cypress mulch, on the other hand, is more resistant to decay and can last longer than eucalyptus mulch. The choice between the two will depend on your specific needs and preferences.

Could eucalyptus mulch have a negative impact on soil health?

No, eucalyptus mulch does not have a negative impact on soil health. In fact, it can help to improve soil health by providing organic matter as it decomposes. This can help to increase soil fertility and promote healthy plant growth.

Is eucalyptus mulch a suitable choice for landscapes in regions with high humidity like Florida?

Yes, eucalyptus mulch is a suitable choice for landscapes in regions with high humidity like Florida. Its absorbent properties can help to retain moisture in the soil, which can be beneficial in humid environments. Additionally, its natural insect-repellent properties can help to protect plants from damage caused by pests.