If you love your Monstera but you’ve noticed that it’s looking sickly, you might be wondering what could be wrong with it. Unfortunately, these plants are susceptible to being over-watered and this can cause problems.
Monsteras do not like to be over-watered, and if you have been too zealous about giving your plant enough to drink, it may start to suffer from root rot. This is a serious condition that can kill even a mature, healthy plant, and you will need to take prompt action if your Monstera has it.
What Causes Root Rot?
Root rot occurs when the plant’s roots are kept wet for too long and fail to get enough oxygen. The roots will then start to rot, and fungus will establish itself on them and start spreading throughout the pot. This is because the soil around the roots will become anaerobic (lacking in oxygen), and this is bad for the plant.
It is bad for all plants, but particularly so for plants such as Monsteras. These evolved to grow in loose, airy soil, and they dislike having wet, oxygen-starved roots. Indeed, Monsteras produce a lot of aerial roots simply so that they can access plenty of oxygen.
They still need loose, well-draining soil around their subterranean roots, however, and these aerial roots are not a substitute for suitable pot conditions. If your container is getting too wet, your Monstera could get root rot.
In general, root rot is caused by over-watering, but some other problems can also cause it, so let’s explore them.
Over-Watering
The commonest cause of root rot is over-watering. You should always make sure that your Monstera needs a drink before you supply one.
To do this, push the tip of your finger into the surface of your plant’s soil. If the soil is dry to around an inch down, the plant will enjoy a drink. If it is still wet, wait for a few more days before watering it.
You should use this method rather than watering on a schedule. Your Monstera will need different amounts of water at different times of the year, so it’s important not to just tip water into the pot on a certain day of the week.
Reduce your watering routine in winter, because your plant will turn dormant or nearly dormant at this time, and won’t need as much to drink. Similarly, increase it in mid-summer, when there is likely to be a lot of evaporation and your plant is growing quickly.
The more you over-water your plant, the higher the risks of it getting root rot are.
Over-sized Container
Many people are tempted to put their Monsteras into large pots to help the plants grow well. This seems like a logical way to reduce the need for repotting the plant and ensures that the Monstera has plenty of room to grow – but it isn’t actually a good idea at all.
A deep container massively increases the risks of over-watering your Monstera, because there will be a lot of space at the bottom of the pot and it will not be clear where the Monstera’s roots are.
This makes it very difficult to judge whether the plant needs water or not. You can still check whether the surface of the soil has dried out, but if there is a lot of residual water beneath the plant, you are much more likely to over-water it.
It’s also true that the soil below the plant’s roots is likely to stay wet for a lot longer – because the plant isn’t drinking the water. This makes it even more difficult to judge when the plant needs a drink.
You should therefore be careful when choosing your Monstera’s container. Put it in a pot that is a little bigger than its root ball, but not significantly. Monsteras prefer to be a little pot-bound and will grow better if their roots are lightly constricted by the size of the pot. Do not use a pot that is too large for it to cope with.
Keep following this rule whenever you pot your Monstera into a larger container. This should be done every two or three years until the plant is mature, and then you can stop repotting it to keep your plant’s size restricted.
Poor Soil
If your Monstera’s soil isn’t suitable, this will also lead to root rot issues. You want the soil to pull moisture away from the roots and allow it to wash out of the pot within a reasonable amount of time; this will ensure that your plant’s roots dry out and get access to oxygen.
Heavy, poorly-draining soil will not make your Monstera very happy. They do not like ordinary compost, clay, or other soils that absorb and cling to moisture, and they are far more likely to rot if they are planted in an unsuitable mixture.
You should instead choose a commercial aroid soil, or mix your own version of an aroid soil. You can do this by combining things like orchid bark, coconut coir, vermiculite, perlite, and a little rich compost in a pot.
The orchid bark and coconut coir will encourage water to run out of the pot, particularly if you place a layer of gravel at the bottom. The vermiculite will absorb some water and release it back to the Monstera slowly over the next few days, so you don’t have to water it again immediately.
Choosing the right potting medium for your plant can make a massive difference in how well it grows and how unlikely its roots are to rot. The better the soil drains, the safer your plant will be.
Don’t leave your Monstera in ordinary compost; this holds onto too much water. If you can’t get coconut coir or orchid bark, consider mixing some gravel and sand through the pot; this will not work as well but will be better than using neat compost.
Poor Drainage
As well as drainage in terms of the potting medium, you need to think about the drainage capacity of the container you provide. If you plant your Monstera in a pot with no drainage holes, it will very quickly start to suffer from root rot.
Ideally, your container should have plenty of large drainage holes so that the water can run out freely. Regularly check that these holes have not become blocked, and that water is still able to run out of the bottom of the pot.
If you want to use a pretty container with no drainage holes, you will either need to drill some, or you will need to use it as a cachepot – the outer container. Use an ordinary pot with plenty of holes inside it so that your Monstera can still drain.
If you are using a cachepot, make sure you are emptying it, rather than allowing water to remain in it. Wait for about half an hour after watering to allow plenty of water to run through into the cachepot, and then empty it.
What Are The Common Signs Of Root Rot?
Many of the common signs of over-watering are – frustratingly – similar to the signs of under-watering. This makes sense, however, because roots that have started to rot cannot take up water effectively anymore.
This means that the plant can be sitting in water, and yet unable to access any of it. Because plants absorb nutrients at the same time as water, this deprives them of both nutrients and the water needed to maintain their structure.
There are multiple symptoms of root rot, including yellowing leaves, cessation of growth, wilting, root discoloration, black leaf spots, a bad smell, and a mushy stem.
Sign One: Leaf Yellowing
Leaf yellowing is often one of the earliest signs that your Monstera’s roots are starting to rot. Monsteras should have bright green, full foliage, with no yellowing on their leaves. If you see a pale tinge creeping over some of the leaves, this is a sure sign that something is wrong.
Yellowing leaves are not only caused by root rot, but they often are. If your plant’s foliage is losing its luster, therefore, you should check it for root rot.
Sign Two: Cessation Of Growth
Has your Monstera just stopped growing lately? Root rot will cut off the plant’s access to nutrients, and without nutrients, it cannot grow. If your plant suddenly seems to be struggling to put out new leaves and stems, it may be without the necessary resources for growth.
Your Monstera’s growth will also slow down in the winter or if it isn’t getting enough light, so you shouldn’t automatically assume that it has root rot without checking the other conditions first, but lack of growth is something to be aware of and concerned by.
Sign Three: Wilting
Wilting is probably one of the most significant signs of root rot, and it’s also a misleading one. Many people, if they see their plant wilting, assume that it needs more to drink. This is logical because limp leaves do mean that the plant isn’t getting enough water.
However, limp leaves can be a sign that you have over-watered your Monstera just as often as they are a sign that you have under-watered it. That might sound contradictory, but remember that when Monstera roots rot, the plant can no longer take in water.
That means your plant can be dying of thirst even though it is sitting in water. Without healthy roots, it cannot drink, no matter how much water is in the soil.
You should therefore be cautious if your Monstera seems to be turning limp much more quickly than you would expect after being watered. It may be a sign that the plant has had too much to drink and its roots are not in a fit state to soak up more water. Check the moisture levels in the soil carefully before giving the plant a drink.
Sign Four: Root Discoloration
You will have to take the plant out of its container to check the state of its roots, but this is the surest way to tell whether the plant has got root rot or not.
Start by checking whether the soil is wet. If it is completely dry, it’s highly unlikely that your plant has got root rot, but if it’s wet, you need to loosen the soil around your plant’s roots and then carefully tip the plant out onto a mat or plastic sheet. Remove the soil until you can inspect the roots.
Healthy Monstera roots should be cream or light in color, and should be firm to the touch. There should be no odor, except perhaps the smell of earth.
Rotting Monstera roots will turn brown or black and mushy. They will lose their structure, and if you touch them, they will feel wet and mushy, like sponges. If the roots look like this, your Monstera definitely has root rot.
Sign Five: Black Leaf Spots
Sometimes, black leaf spots can be a sign that your plant has root rot. Again, this will be caused by the fact that the plant cannot get enough nutrients from the soil to build and maintain healthy foliage.
This leaves it vulnerable to bacterial infections, which can cause spots to appear on the leaves. These may be surrounded by yellowing circles, and they will get worse as the root rot progresses.
Sign Six: A Bad Smell
If you notice a funny smell around your plant’s pot, this is another key sign that the roots are rotting. The conditions in the soil will turn anaerobic if it is wet for too long, and this will kill off the normal, healthy bacteria that exist in the soil, replacing them with other bacteria.
Anaerobic bacteria often smells bad, and this smell will permeate through the soil. The rotting roots will have an unpleasant, moldering scent.
You might notice this particularly when you water the plant, as this will disturb the soil and release gasses from it. If you do catch a whiff of something unpleasant either during watering or when you pass your plant’s pot, stop and investigate what’s going on.
Sign Seven: A Mushy Stem
If your Monstera has soaked up excessive amounts of water, its stem will sometimes become mushy as it too starts to rot. This is likely to be a bigger issue if the air around the Monstera is too humid because this will make it harder for the plant to get rid of the excess water through its leaves.
If the main stems of your plant have turned soft and mushy, you have a serious rot problem on your hands. You will need to act swiftly if you are going to successfully save your plant. Do not ignore a mushy, soft stem, even if only one seems sick and the rest of the plant appears healthy.
Often, if the stems of the plant have started to turn mushy, it will be beyond saving, but you can still try.
How Can I Check If My Monstera Has Root Rot?
All of the above signs should indicate whether your Monstera has root rot. Individually, many can be explained by other issues, but if you are seeing multiple issues, it is likely to be root rot.
The surest way to determine whether your plant’s roots are rotting is to remove it from its pot and inspect the roots. However, you don’t want to disturb and shock your Monstera unnecessarily, so check for the other signs first.
You should also take into account your watering technique. How often do you water your Monstera and how do you check if it needs a drink before you water it? If you know you are cautious about watering and you only give it a drink when the soil is dry (and you have checked things like drainage), it’s unlikely that your plant has root rot.
However, if you water on a schedule or you haven’t checked the drainage situation recently, look for the seven signs of root rot, and tip your plant out of its pot to check its roots.
What Should I Do To Treat Root Rot?
Treating root rot is relatively straightforward, although you may find that your plant is too far gone to save it. Acting quickly will be crucial; the longer you wait, the more the roots will rot, and the more risk your Monstera faces.
You should therefore make a swift assessment of the situation, and then take action to deal with the root rot. This will involve repotting the plant, which can be challenging with a large Monstera.
Step One: Remove The Plant From Its Pot
You should spread a plastic sheet out to protect your floor, and then loosen the soil in your Monstera’s pot. Once the soil is loose, gently tip the pot onto its side and begin working the Monstera out.
Make sure you ease its moss pole or trellis out alongside the plant so you don’t damage its stems. This can be challenging, so consider getting someone to help you if you are struggling.
Tip the plant carefully onto the plastic sheet, and then begin brushing the soil off the roots. If the soil is very wet, this may prove tricky, but get as much off as possible so you can see the roots.
Next, you are going to need to wash the roots. It may be easiest to put your plant in the bath or the base of a shower if it’s not too large.
You can also spray a large Monstera down with a hose or even a spray bottle. You must get rid of all the soil, as it is contaminated and could reinfect the plant if any is leftover on the roots when you repot it.
Step Two: Inspect And Cut The Roots
Once the roots are free from soil, take some time to inspect them and identify the unhealthy roots. Remember, healthy roots will be white and firm, while unhealthy roots will be brown and mushy.
Next, get some boiling water and some sharp, sterile scissors. Use the scissors to cut away the rotten roots, removing them from the plant. Try not to touch the healthy roots with the rotten roots, as they will spread bacteria to them.
Remove all of the rotten roots, pausing to sterilize the scissors in the boiling water from time to time. This will reduce the risk of damaging the healthy roots. If the Monstera has bad root rot, it might feel like you are taking a dangerous amount of its roots away, but these roots are not serving the plant anymore and need to be removed if it is going to recover.
Once you have cut away all of the rotten roots, they can be composted.
Step Three: Disinfect The Roots And Let Them Dry
Your next step is to leave the healthy roots to dry out. Even these are likely to be very wet, and they now need to be left exposed to the air. However, it’s a good idea to disinfect them before you leave them.
You can either use a commercial fungicide or a homemade sterilizing liquid. Mix two tablespoons of peroxide into two cups of water, and then rinse the roots with this solution. It will kill the fungi. Once you have done this, rinse the roots in clean, fresh water, and then leave them to dry.
You can blot at the roots with dry paper towels if you like, but often, it’s best to just leave them exposed to the air for a few hours. Do not put the plant in direct sunlight or a hot place while its roots are exposed.
Step Four: Repot
Get a suitable container with good drainage holes, and make sure it is clean. Add a layer of gravel to the bottom of the container to improve the drainage, and then fill it with a mix of orchid bark, vermiculite, compost, coconut coir, etc. Do not reuse any of the old soil; it is contaminated and could cause the root rot to recur.
Make a hole in the center of the pot and work your Monstera’s root ball gently into it, handling it with care. Once the plant is in place, fill in the soil around its roots and pat it down (do not press).
Step Five: Prune The Plant
It may seem excessive to remove some of your plant’s foliage as well as its roots, but this increases its chances of survival. You should aim to remove about a third of its leaves, using sterile pruning shears.
Leaves are important for the plant’s survival, but they have quite high maintenance costs. With fewer roots, your Monstera will struggle to support all of its established leaves. It is best to remove some so that it can focus its energy on building new roots, rather than struggling to soak up enough water and food to support its current foliage.
If you don’t cut the leaves back, you will likely notice them wilting over the next few weeks anyway. Unless you have removed a very small number of roots, your plant simply won’t be able to supply all its leaves. You can minimize the stress by pruning the plant as soon as it is in its new pot.
Step Six: Put It Somewhere Suitable
As long as your Monstera was in a good position, it’s often best to put it back where it came from, as this will reduce the environmental changes and the overall shock. If the positioning wasn’t suitable, however, try to find a new spot for it, with plenty of bright, indirect light to encourage new growth.
It may be quite some time before your plant gets over the shock and damage. It will need to put lots of energy into establishing new roots, so don’t expect it to resume its leaf growth again for at least a few weeks. Make sure you are only watering it when the soil is dry, and keep an eye on the drainage to avoid the issue recurring.
Will My Plant Survive Root Rot?
It’s hard to know whether a Monstera will survive root rot or not because it depends on how bad the rot has got. There are generally three stages:
Early root rot: your plant will start to grow more slowly, and the leaves will wilt and begin turning yellow.
Medium root rot: a bad smell will start to come from the plant’s pot, black spots may appear on the leaves, and the roots will begin to change color.
Advanced root rot: the stems will turn mushy and the roots will be mostly dead and black beneath the soil.
You should be able to save a plant that is in the early stages of root rot, especially if it is a strong specimen. With medium root rot, it will be harder and it will depend on how healthy the plant was. It is unlikely you will be able to save a Monstera that has reached the advanced stages, although you may still wish to try.
When you are inspecting the roots, you should get a good idea of how likely the plant is to survive. The more root you are removing, the lower the Monstera’s chances of survival are.
However, you shouldn’t leave damaged roots on in the hopes that this will improve your plant’s chances; these roots are nothing but a liability. All damaged roots must be removed to give the plant the best chances of recovery, even if this seems excessive.
Early detection is key to helping your plant survive root rot, but you have little to lose if you find a plant in the advanced stages – you may as well try to save it. Just be aware that your chances of success will be low and your plant may die.
Can I Prevent Root Rot From Happening?
The best way to prevent the risk of root rot from occurring is to water your plant only when the soil feels dry. However, you should also pay attention to the drainage in your plant’s pot, as even a good watering routine can be foiled by poor drainage.
Make sure water runs freely out of your plant’s pot when you water it, and check the soil moisture from time to time. If the plant seems to stay wet for more than a few days after being watered, there may be a drainage issue.
Being vigilant and aware of this potential problem is the best way to prevent root rot from occurring. You should also familiarize yourself with the common early signs of root rot, and look out for these at all times.
Should I Take A Cutting?
If your plant is looking really bad when you take it out of its pot, you may feel that you can’t save it. However, all is not necessarily lost. If your plant still has some healthy stems and leaves, try taking a cutting from it.
You can do this with a pair of sharp, sterile pruning shears. Cut the stem below a growth node, with one or two leaves remaining on the stem. Place this stem in either suitable soil or some water, and wait for the growth node to root.
Note that you must choose a healthy growth node and leaf to maximize your chances of success. You may wish to do this as an insurance policy even if you expect to be able to save the mother plant.
Conclusion
Root rot is a very serious problem for Monsteras, and it can kill even a large, healthy specimen in surprisingly little time. You need to make sure you are only watering your Monstera when it needs a drink, and keep an eye out for the signs of root rot. Being vigilant should mean you can save your plant even if problems do occur.