Skip to Content

How To Get Rid of Mold on a Bonsai Tree | Ultimate Guide

Get Rid of Mold on a Bonsai Tree

Mold can form on your bonsai tree, and it is important to get rid of the mold as quickly as possible. If you leave the mold on your bonsai tree too long, then it will start to rot and kill your plant.

This blog post will teach you how to identify if there is a problem with mold on your bonsai tree, what types of diseases your bonsai may have, and what steps you need to take in order to get rid of the mold that has already formed.

Continue reading if you want to know how to get rid of mold on a Bonsai tree.

Getting Rid of Molds on a Bonsai Tree

Molds are a type of fungus that typically grow on decaying organic matter. They can also form on living plants, and this is often the case with bonsai trees.

Molds can cause a number of problems for your bonsai tree, including: rotting the wood, weakening the branches, stunting growth, and causing leaf drop. If you have a mold problem on your tree, then it is important to take action right away.

There are a few steps that you can do in order to get rid of molds on your bonsai tree.

  1. If you have a bonsai tree that is infected by molds, the first thing you must do is remove the infected leaves. You can do this by plucking them off, but never just tear it off because you might take a portion of the branch or trunk together with it. You should also be careful when removing the diseased parts of your bonsai tree to avoid further damage.
  2. You will also want to make sure that you water your bonsai tree regularly, as this will help to prevent mold from forming in the first place.
  3. If the mold has already formed on your tree, then you will need to take steps to remove it. One way to do this is by using a fungicide spray. You can also do this by removing the infected leaves first, then after, clean the area around the wound with a disinfectant. This will help stop the spread of the mold spores to other parts of the tree.
  4. Be sure to follow the instructions on the label carefully, and always wear gloves and goggles when spraying the fungicide. Fungicides are available in liquid, powder, or aerosol form, and can be bought from most garden stores.
  5. You may also want to consider taking your tree to a professional bonsai gardener for help.
Get Rid of Mold on a Bonsai Tree

Preventing Molds on a Bonsai Tree

Molds can form on your bonsai tree for a number of reasons, including: high humidity, poor air circulation, over-watering, and too much fertilizer. There are a few things that you can do in order to prevent mold from forming on your tree.

  1. The first step is to make sure that you are watering your tree correctly. You should only water the soil when it feels dry to the touch, and be sure not to over-water.
  2. You should also provide good air circulation around your tree by using a fan or by placing it in a sunny spot.
  3. You can also reduce the humidity around your tree by using a dehumidifier or air conditioner.
  4. And finally, be sure not to over-fertilize your tree, as this can also lead to mold growth.

If you follow these tips, then you can help to prevent mold from forming on your bonsai tree. However, if you do end up with mold growth, then it is important to act quickly in order to prevent the problem from getting worse.

The Two Types of Molds on a Bonsai Tree

There are two types of molds on a bonsai tree – the pathogenic and nonpathogenic molds.

Pathogenic molds are the ones that can cause diseases in plants. They can infect the leaves, stems, and fruits of the bonsai tree, making them rot and wither. These molds can also cause root rot, which will kill the tree.

Non Pathogenic molds, on the other hand, are not life-threatening for the bonsai tree. They are actually beneficial because they help maintain proper humidity and promote release of nutrients in the leaves, stems, and fruits of the bonsai tree.

Molds on a Bonsai Tree – Where Do They Come From?

Molds come from fungi that are naturally present in our surroundings. They are everywhere… under the soil, on the walls of our rooms, and even inside our body. But because molds come in different colors and appearances, it is difficult to tell which mold is good or bad just by looking at them.

  • Mold growth on bonsai trees comes from leaves that have been infected by fungi spores.
  • These spores are carried to the bonsai tree through the air, usually by rain drops. But it can also be brought by insects that have come into contact with these fungi during their trips outside the house.
  • When left untreated, mold growth will cause injury to the leaves of your bonsai tree and even kill it.

White molds, for example, can cause the leaves to turn yellow and drop off.

Black molds can make the leaves look wet and slimy, and eventually rot them.

Get Rid of Mold on a Bonsai Tree

How to Identify if Your Bonsai Tree Has Molds

Mold problems are very common in bonsai. If you have a new bonsai, it may look clean on the surface for quite some time but molds can be hiding out of sight underneath your soil or moss. It is important to be able to identify mold problems and take corrective action as soon as possible.

There are a few ways to identify if your bonsai has molds.

  1. One of the most obvious ways is if you see any evidence of mold on the surface of the soil or moss. Mold will look like small, black spots on the surface of your soil or moss that can be easily wiped away. If you see any area where the surface is damp, there may also be molds growing underneath.
  2. If you dig up your bonsai to take a closer look at the roots and feel them with your fingers, you may notice that they are slimy. This is evidence of molds. Underneath the soil, mold will appear as webs and small fungus-like structures.
  3. Another way to identify mold problems is by looking at the underside of your bonsai leaves. If you see any spots, it is an indication that molds are growing underneath.
  4. You also may notice that your bonsai will have yellow leaves or leaf drop. This is a sign that the molds are taking their nutrients from your plant and it can cause permanent damage if you do not take action immediately.

If you find molds inside of your bonsai pot or tray underneath your bonsai tree’s roots, it is important to take corrective action immediately and clean up all moldy areas. Molds can spread very quickly and will damage your bonsai tree if not taken care of immediately.

What Happens if You Don’t Remove the Mold on Your Bonsai Tree?

If you don’t remove the mold on your bonsai tree, it will continue to grow and spread. The mold can cause damage to the tree’s leaves, branches, and roots. If the mold is not removed, it can eventually kill the tree.

Your bonsai will…

1. Lose its leaves – The mold spores will form on the leaves and eat away at them. Once this happens, the leaves die and fall off. The more that the mold spreads, the more your bonsai tree will lose its leaves-eventually killing it if you don’t remove the mold.

2. Have stunted growth – You have to remove the mold so that it won’t spread. When you don’t, your bonsai’s growth can easily be stunted. The leaves will no longer be able to produce energy for the tree to survive.

3. Have yellow leaves – The mold will kill the leaves, which in turn will affect your bonsai tree’s ability to photosynthesize. The leaves will become yellow and fall off because of this.

3. Die – If the mold isn’t removed, it will eventually kill the tree. The leaves will die and fall off, the branches will stop growing, and the roots will rot. This will cause your bonsai to die.

Other Diseases that Affect Your Bonsai Tree’s Health

Bonsai trees are susceptible to a variety of diseases, including the three most common: viruses and fungi, aside from the expected molds. It’s important to identify these diseases correctly because each one requires a different treatment.

Viruses are a common problem for bonsai, especially when using wild collected material. In general, viruses won’t kill your tree but instead will cause problems with the foliage that may never go away. Symptoms of viral infection include mottling, ringspots and mosaics in the leaves. There is no treatment for a bonsai tree infected with a virus. Once symptoms occur, the virus will remain in the tree for life and can be transmitted to other trees through infected cutting or grafting materials.

Fungi are another group of pathogens that affect bonsai trees. Most often they show up as black spots on leaves or roots, but some fungi attack the trunk, and other fungi rot the roots and lower trunk. The most common fungus disease is phytophthora, which generally enters through wounds or pruning cuts. Black spots on leaves may indicate anthracnose fungal infection, while white powdery areas on leaves often mean powdery mildew fungus is involved.

Fungi can be treated with fungicides, but it is important to correctly identify the fungus involved in order to use the correct fungicide. Root and lower trunk rot can often be prevented by keeping the soil free of surplus water.

Molds are a common problem with bonsai, especially during damp weather conditions. They can cause leaves to turn yellow or black and may grow on the soil surface. Fungicides may be used to control mold, but it is important to first determine which type of mold is present.

There are other diseases that affect bonsai trees, consisting mostly of viruses, fungi and molds. And like mentioned before, each requires a different treatment method to rid off unwanted organism growths. So before anything, be sure to know and understand the signs of such a problem. Remember, early detection is key!

Get Rid of Mold on a Bonsai Tree

Removing Molds from Bonsai Roots

Mold is fungus that grows in the absence of air(anaerobic). Molds are generally dark colored threadlike vegetation. Molds are common on the underside of tree bonsai pot lids and rocks, where they grow because water accumulates in these locations.

  • Pot lids and rocks that are placed under trees in bonsai training pots seem to encourage the growth of mold because they prevent good air circulation around rootystems, which can result in a buildup of moisture on their undersides.
  • Molds can also grow on bonsai roots if they are kept too wet or if the soil is not drained properly.

If you discover mold on your tree’s roots, you will need to remove it as soon as possible. One way to do this is to cut away the affected area of the root with a sharp knife or pruning shears. Be sure to disinfect the cutting tool before and after use with a household disinfectant such as bleach or alcohol.

If the mold is widespread, you may need to repot the tree into a new soil mix. Be sure to use a pot with drainage holes and a soil that will drain water quickly. You can also reduce the amount of water you give your tree until the mold has been removed and the roots have had a chance to heal.

Bonsai Mold and Fungus

There are many reasons why bonsai may develop mold or fungus, and some of these are preventable. One of the most common causes is poor drainage, which can lead to waterlogging. This creates a perfect environment for the growth of mold and fungi. Other causes can include over-watering, under-watering, excessive humidity, insufficient light, and the use of poor-quality soil.

Since mold and fungus can be a serious threat to your bonsai, it is important that you get rid of any problem as soon as possible. In this article we will discuss how to identify these problems and what you need to do if you find them in your bonsai:

Identifying Mold and Fungus

The first step in getting rid of mold or fungus is to identify it. Here are some of them:

  • Rust – This is a reddish brown fungus that appears on the leaves of trees. It can cause the leaves to discolor and drop off.
  • Mildew – This is a white or gray fungus that typically appears on the leaves or stems of plants. It can cause the leaves to wilt and die.
  • Leaf spot fungus – This is a fungus that causes small spots to appear on leaves. It can cause the leaves to drop off or turn yellow and fall off.
  • Black spot fungus – This appears on leaves, twigs and branches of trees. It is also known as tar spot fungus.
  • White fungus – This fungus appears on the surface of rocks or soil and is typically white in color. It can also grow inside trees, causing them to rot.

Being able to identify these problems is important because it allows you to know which steps you need to take in order to get rid of them.

Get Rid of Mold on a Bonsai Tree


In this article, we have discussed how to get rid of mold and fungus on bonsai trees. We have looked at the different types of mold and fungus that can affect bonsai, as well as the signs that they are present. Finally, we have outlined steps you can take to remove the mold or fungus and prevent it from coming back.