Can I Mix Mulch With Potting Soil? (Explained)

by Alex Kountry
Updated on

To have healthy plants, it is important to know the do’s and don’ts in handling them. One way to optimum productivity of your plants is through mulching.

Mulch is a layer of material applied to the surface of the soil.

Reasons for applying mulch include conservation of soil moisture, improving fertility and health of the soil, reducing weed growth, and enhancing the visual appeal of the area.

Knowing how and where to apply mulch to your soils is very important. So, can I mix Mulch with potting soil? Want to get an answer to this? Then keep reading!

Can I Mix Mulch With Potting Soil?

Can I Mix Mulch With Potting Soil

Yes, mulch can be mixed with potting soil.

This helps to increase the soil’s organic matter. Mulch helps to keep the soil moist and cool, this provides nutrients for plants, and it also helps to control weed growth.

When growing plants, however, it’s best to use bark mulch mixed with the potting soil. It’s important to avoid growing plants in wood mulch.

Thick levels of mulch have been observed to suffocate plant roots. This is because plants, like humans, require air to survive.

However, they wilt when their root systems are covered beneath large levels of mulch, which reduces the amount of air in the soil.

This article contains vital information about mulch and its benefits to soils. Keep reading!

How Is It Done And What Are The Benefits?

Mixing mulch to potting soil is quite easy if you follow the process correctly. Here are the steps in mixing mulch to potting soil.

  • First, make sure you use the correct amount of mulch when mixing. Too much mulch in the soil can cause nitrogen deficiencies. As a result, it is always recommended to use less mulch in comparison to the amount of potting soil.
  • It’s best to add the mulch to your potting soil gradually. Apply a small amount of mulch to the first 2 to 4 inches of potting soil with a shovel.
  • You also have to ensure that the potting soil completely covers the mulch.
  • Now, add more layers of potting soil and even speed it up.
  • Continue by spreading a thin layer of new mulch evenly over the potting soil.

Told you mixing mulch to potting soil is super easy. There are, however, some precautions to consider when doing so. Let’s go over some crucial safety precautions to take;

  • Don’t add too much mulch as earlier said this is to prevent nitrogen deficiencies.
  • Ensure you use only organic mulch when mixing into the potting soil.

Having discussed the steps of mixing mulch with potting soil, it’s time to reveal the benefits of mulch to potting soil. Let’s dive right in!

1. It increases organic matter

The combination of mulch and potting soil ensures that microorganisms and bacteria produce compost that is high in organic matter.

This results in healthier plants that are more resistant to disease. It also provides a much better environment for the soil’s natural population of beneficial flora and fauna.

2. It reduces soil compaction and erosion

Mulch is composed of elements that protect the soil against water and wind erosion.

Furthermore, it reduces soil compaction, which can negatively impact crop roots. Increased soil compaction can result in reduced plant growth and development.

3. It ensures improved soil aeration and drainage

The mixture of mulch and potting soil can help to increase soil drainage. When microorganisms and bacteria break down the mulch, they produce compost.

This will also provide a much better environment for the soil’s natural population of beneficial flora, such as earthworms and insects.

When these organisms move through the soil, they help to create air spaces and increase drainage.

4. It regulates the temperature of the soil

This is one amazing benefit of mulch to soils. The temperature level of soil can improve the overall growth and health of your plant. 

Since mulching protects the soil surface, it helps to keep the soil temperature stable. 

5. It improves soil nutrition levels

A healthy soil has been well-nourished. Mulch enriches the soil with nutrients, which in turn nourishes the plants, making them healthier and stronger.

Mulch, in general, is very beneficial to soil, even when it’s old. Mulch slowly decomposes, releasing valuable minerals and organic materials into the soil.

Here is an article I wrote on how to rehydrate dried potting soil

Can You Mix Bark With Potting Soil?

Yes, you can mix bark with potting soil as well. Mixing bark with potting soil is a way of providing the right amount of water, air, and nutrients to support healthy plants.  

Pine bark is often used in the potting mix but bark chips can also be used. It has a way of preventing the mix from sinking when it is wet.

Some of the benefits of mixing bark with potting soil include; 

  • It improves the aeration and drainage of commercial potting mix or seed-starting mix.
  • Barks are cheap and more coarse than Perlite, which makes it more preferred.
  • Its water retention ability is top-notch.

When it comes to mixing barks and potting soil, you can use any ratio you choose depending on how much air your roots need.

You don’t have to mix your bark and potting soil in a 50/50 ratio.

The same goes for mulch.

Too much mulch on the soil might be harmful to the plants. It reduces air circulation, which can lead to inadequate soil aeration and even plant death.

Adding roughly 20% – 30% bark to potting soil is a good strategy to cut costs and extend the life of the soil.

What Is The Best Mulch To Mix With Soil?

There are two types of mulch which are; Organic and Inorganic mulch.

Organic mulch is a perfect mix with soil. Organic mulches are mulches that will break down over time which will increase soil fertility and boost the growth of your plants.

Inorganic mulch on the other hand are mulches that are synthetically made such as rubber mulch, stone mulch (aka rock mulch), and landscaping fabric.

These mulches do not break down over time and even if they do, the chemicals contained in the mulch can harm plants when released into the soil. 

Not to mention, the chemicals can get their way into the fruits or vegetables and your plate. This is why you should only consider mixing organic mulches into the soil.

Knowing what type of mulch you have is a good start in preventing any unwanted events. 

Also check out this article I wrote on is potting soil homogenous or heterogenous

Can You Put Mulch In Potted Plants?

Adding a layer of mulch to any potted plant can be a simple and easy way to make plants look much better and to help keep them healthy.

Mulching can also be a great way to conserve soil moisture and encourage new healthy growth in plants with wilting stems.

Similar to how mulch is important for outdoor plants, indoor potted plants can also benefit from a layer of mulch.

Certain types of mulch, such as those made from materials like sawdust, pine needles, and grass clippings offer amazing benefits to plants. Some benefits include;

  • Decomposing and releasing nutrients into the soil.
  • They also protect the plant’s roots from the sun.
  • Furthermore, they promote water retention.

Can I Mix Mulch With Garden Soil?

No, Mulch cannot be mixed with garden soil, this is because garden soils are inorganic. Mulches don’t do well with inorganic soils. 

These mulches do not break down in inorganic soils and even if they do, the chemicals contained in the mulch can hurt plants when released into the soil. 


Mixing mulch with potting soil is a very welcomed process, it has no side effects whatsoever.

However, it’s important to note that mulching has to be exclusively organic, this explains that it’s okay to mix mulch with potting soil. 

With that being said, it is clear that mulch shouldn’t be mixed with garden soil.

Because it is an inorganic soil, the chemicals in the mulch might be harmful to plants if they are released into the soil.

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About the author

Alex Kountry

Alex Kountry is the founder of HayFarmGuy and has been a backyard farmer for over 10 years. Since then he has decided to write helpful articles that will help you become a better backyard farmer and know what to do. He also loves to play tennis and read books


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