Root rot in monstera plants is caused by a fungal infection, which is usually due to overwatering the plant. When the roots of the plant become waterlogged, it creates an oxygen-deprived environment that effectively suffocates and damages the roots. The damaged roots then become susceptible to opportunistic pathogens that worsen the rot.
There are a lot of factors that can contribute to root rot, but it all boils down to the presence of too much water in the soil and around the roots of the plant.
In this article, we will discuss the different causes of root rot and how to save an affected monstera plant.
What are the signs of root rot in a monstera plant?
1. Black spots
If your monstera has black spots on its leaves, it might have root rot. This sign means the infection from the pathogens has traveled up into the rest of the plant and is now affecting the stem and leaves. These black spots usually have a yellow halo around them.
2. Rotten smell
Because the roots are decaying, it is no surprise that there will be a distinct foul smell emanating from them. It is a good thing if you can smell this odor while the rest of the plant looks healthy, because that means you have caught the rot before it has made its way to the rest of the plant. This way, you can treat the infection before it becomes fatal.
3. Leaves turning yellow or brown, and wilting
The leaves of a monstera suffering from root rot will turn yellow or brown, because the roots are damaged and are unable to absorb water and nutrients effectively from the soil. The overall health of the plant is thus affected, which is why the leaves will start dying off the longer the rot is left untreated.
The leaves will also be wilt, due to the lack of nutrients.
4. Brown or black, mushy roots
This sign can only be spotted if you remove the plant from the soil. Some people discover root rot by accident when they are repotting their plants.
The roots turn brown or black and become soft and mushy because they are actively decaying, due to being waterlogged and infected with fungi. The roots will also break off easily when you separate them from the soil.
5. Slow growth
Every growth season, your monstera will shoot new leaves. If you notice that your plant has not had any new foliage in the past few months, its growth may have stunted and this could very well be due to root rot.
What causes root rot in monstera plants?
The most common reason monstera plants get root rot is overwatering, and there are several factors that can contribute to this.
Although monsteras like their soil to be slightly moist, it should never be waterlogged or soggy.
Your plant becomes overwatered if you are give it more water than it needs, or if you water it more frequently than it needs. If the pot you are using does not have drainage holes or if the soil in the pot is too heavy or compact, excess water and moisture will be retained around the roots and end up suffocating them. If the pot is too big for the plant, the soil will also hold more water than the plant needs, thereby also overwatering it.
It might seem strange for a plant to get root rot if it is underwatered, but this can happen when the roots have been underwatered for extended periods of time. The roots are so used to a drought-like situation that they become compact and will shrink in size. Because the roots have shrunk, there will be sections of soil that have no roots. When you finally water the plant, the soil will not dry out for quite some time and this could result in root rot.
An overwatered or underwatered monstera will get root rot because its roots have been compromised, and the situation is then worsened by the presence of opportunistic fungi that cause the rot to spread faster to the rest of the plant, and possibly kill it.
The most common species of fungus that cause root rot in monstera plants are the Fusarium, Pythium and Rhizoctonia species.
Often these fungi are already lying dormant in the soil around your plant’s roots, just waiting for the perfect opportunity to strike.
The spores of these fungi can be spread by insects and small animals, or through contaminated gardening tools. Make sure the tools you use to prune or dig up your plants are always sterilized.
Monstera plants normally slow their growth during the winter, and they will need less water than they would during their growth period in the spring and summer.
If you forget to adjust your watering schedule, you might end up overwatering your plant.
The cold temperature and lack of light in the winter also keeps the soil from drying out as quickly as it should, leading to overwatering and root rot.
Can all monstera plants with root rot be saved?
No, unfortunately, there are situations where the plant may be too damaged by root rot, and you are better off disposing of it and starting over with a new plant.
If all of the roots on the plant are dead, you are too late. You need at least some healthy roots to have a chance at salvaging it, because these roots will aid the recovery of the entire plant.
If the plant’s stem has turned brown or black and is soft and mushy, that means the rot has moved up from the roots all the way to the main stem. The stem is no longer able to transport water and nutrients from the roots to the rest of the plant. Sadly, the plant will die in this case.
How do I save a monstera plant with root rot?
Remove the plant from the old pot
Before anything, once you suspect root rot, stop watering your monstera plant immediately.
You need to take the roots out of the waterlogged soil as soon as you can.
Make sure you take the plant out of the old pot slowly, so that you can remove as much of the root system as possible.
Shake and wash off the excess soil from the roots so that you can inspect the roots clearly. If there are parts of the roots that are brown or black, cut them off using clean scissors. Save all of the white, healthy roots.
Spray the remaining roots with fungicide and let the plant air-dry on a dry paper towel on top of a tray.
If you want to reuse the old pot, you can do so, but you should wash and disinfect it properly so that it does not reinfect your plant. Make sure the drainage holes at the bottom of the pot are big enough, and use fresh, well-draining potting soil. You can add perlite or coarse sand to the potting soil to make it more porous and airy.
Once the plant’s roots are dry, you can replant it. Do not water it yet; you want to give the plant’s roots at least a week to recover before watering.
Place the plant in a spot where it can get bright, indirect light for about six hours a day.
It will need a good source of light so that it can photosynthesize effectively and recover faster.
Monstera plants get root rot because of various factors that cause their roots to soak in soggy soil. This can be due to overwatering, underwatering, or cold temperatures. When the plant’s roots are damaged, opportunistic fungi are quick to attack and worsen the rot until it consumes the entire plant.
If there are still some healthy roots, you can save your plant by removing the infected roots, spraying the remaining roots with fungicide, letting the plant air dry and replanting them in fresh soil, in a pot that has drainage holes.
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