Spider plants are low maintenance, easy to care for indoor plants. This is what makes them among the most popular houseplants around.
But while they are generally tough and resilient, they have one weakness, spider plant root rot.
This is something every home gardener needs to be aware of and work to avoid. That’s because root rot can be fatal for this plant.
What causes spider plant root rot? The plant hates wet feet. Overwatering, incorrect soil and lack of drainage are usually the main causes.
As such, it is important to allow the soil to dry between waterings. Similarly, make sure to use well-draining soil and a pot with drainage holes at the bottom.
Causes of Spider Plant Root Rot
Overwatering is more often than not the number one reason for spider plant root rot.
That’s because many people end up being too generous when watering their houseplants. In part, it is probably because of the misconception that plants need to be watered on a daily basis.
However, that’s not the case for most houseplants, the spider plant included.
If you do that, you’ll likely end up with spider plant root rot.
That’s because the plant does not need a lot of water.
Thus, it is best to wait until the soil is 50% dry from the top before adding more water.
There’s no need to water it more often than that.
In fact, watering too frequently is downright dangerous.
Plants depend on their roots to sustain themselves. That’s because the roots are what absorb water and nutrients from the soil.
But what many people don’t know is that roots need just as much oxygen as they need water.
So, it is important to balance air with water to keep roots healthy.
When you water too often, the excess moisture will fill up all the air pockets in the soil. In doing so, it pushes out all the oxygen.
This deprives the roots of the air they need. And in its place, they get loads of water.
As a result, the roots end up swimming in water and later will suffocate from the lack of oxygen. If the water does not dry or drain soon enough, the roots eventually die from suffocation.
Then, they will rot.
Rotten roots don’t function anymore. So, the plant will get weaker.
And the more roots rot, the worse off the plant gets.
Thus, it is always a good idea to check the soil before adding water. If you see wet, soggy soil, that’s always a warning sign that you may be overwatering the plant.
As such, wait until the top half of the soil dries before watering the plant.
Lack of Drainage
One of the more hidden causes of spider plant root rot is insufficient drainage.
Here, I’m talking about a pot or planter without any way for the excess moisture to drain. This poses a problem which is like a hidden danger since you’re less aware of it.
Why is this a problem?
That’s because when excess moisture drains from soil, it has to go somewhere.
If the planter has no way to draining the excess water, it will just accumulate at the bottom of the container.
This keeps the soil wet which keeps the roots wet as well.
After a while, you end up with waterlogged soil as more and more moisture builds up at the bottom.
Therefore, it is very important to choose a container with sufficient drainage. This means there should be enough holes to allow excess liquid to drain out.
I also know some gardeners who will drill their own holes at the bottom of their pots.
This way they can customize how much drainage there is.
It is also worth mentioning that many growers will emphasize using terracotta or clay pots instead of plastic.
That’s because of the porous nature of these pots that will allow moisture to pass through.
This does help as well. But from my experience, the difference is not that big to make a huge deal out of it.
Thus, I’d rather you choose the kind of pot or planter you want to use for your plants.
Just make sure that there’s enough drainage at the bottom to let excess liquid drain out.
Soil is another reason for spider plant root rot.
Again, it is closely related to watering.
That’s because once you water the plant, it is up to the soil to retain this water or drain it out. How long it holds the water or how quickly it drains it all depends on the kind of soil you use.
When it comes to the spider plant, it is best to use moist, well-draining soil.
That’s because the plant does not like wet feet.
As such, well-draining soil can quickly drain excess water. This way the roots don’t end up sitting in lots of liquid for prolonged periods of time.
Avoid using heavy soils since they will hold on to too much water.
As a result, this will lead to waterlogging which causes overwatering.
When this happens, the roots end up suffocating due to too much moisture and not enough access to oxygen. And they will eventually die and rot if the water does not dry soon.
Similarly, don’t use garden soil for your houseplants.
Instead, go with potting soil.
Garden soil contains all sorts of things that your indoor plants don’t like. This includes potential pests and disease.
If you like buying your potting soil off the shelf, you can go with African Violet mix.
On the other hand, if you prefer making your own potting mix, you can combine potting mix with perlite or coco coir.
Pot That’s Too Big or Too Small
Another sneaky reason for spider plant root rot is pot size.
Gardeners will choose pots for several reasons. In most cases, it is about looks. This includes the material, texture, color and even design.
At times, size also comes into play but less so.
But from experience, pot size is very important because it affects how healthy your plant is. It also affects the growth of your home.
In general, you want to avoid a pot that’s too big or too small.
Both have their pros and cons.
Instead, choose a pot that is about the right size.
How can you tell?
I like to choose a pot that is 1 to 4 inches wider than the plant’s root mass. In most cases, it is about 2 inches wider. However, for faster growing plants, you can go up to 3-4 inches.
This allows you to start off with the right pot.
On the other hand, if you buy a plant from a store or nursery, they’ll usually come with their own pots. You can use this pot, provided that you debug the plant and quarantine it first before brining it into your home.
From there, you only need to repot the plant when it outgrows the container.
Repotting your spider plant is only needed when the plant gets root bound. You don’t need to do so any time before that except for emergency situations.
And when repotting go up one pot size. This is about 2 inches wider than the current pot.
So, why is pot size so important?
If you keep your spider plant in pot that’s too small, its growth will be limited. Its roots will get crowded in the pot.
And this will prevent it from achieving its full growth potential.
Thus, don’t be surprised to end up with a spider plant that’s smaller than others.
Another downside with a pot that’s not big enough is that as the roots get more crowded, the plant will get stressed.
At the same time, there will be less space for soil as the roots take over the space in the pot.
The problem is that soil is what holds water and fertilizer.
So, the less soil there is, the less water and nutrients it will hold.
This means that the spider plant will eventually not get enough water and nutrients to grow.
As such, it is important to repot the plant once it gets root bound. This gives the roots more space to grow which allows the plant to continue getting bigger.
On the other hand, a pot that’s too big is even more dangerous.
This is why it is important to avoid overpotting your plant. This applies when first choosing the pot as well as when you repot your spider plant.
When you get a pot that’s too big, this will mean lots of extra space between the pot and the roots.
As such, you’ll be filling the pot with more soil.
More soil volume may not seem like a big deal. Unfortunately, it can increase the risk of spider plant root rot.
The reason is when you water the pot, the large volume of soil gets wet.
This means the roots will end up in tons of water that it does not particularly like. Additionally, more wet soil also means it takes much longer for the moisture to drain or dry.
So, the roots end up in more water for much longer periods of time. Sounds familiar?
It’s the recipe for overwatering and waterlogged soil.
The other problem with overpotting is that your spider plant may not grow as planned.
While the larger pot does give the plant the go signal to grow more, the space encourages the root system to get bigger.
Here lies the problem.
Plants only have a limited amount of energy and resources for growth and development.
If it focuses more energy and resources on growing its root system, it means it is spending less on the leaves above the soil.
As a result, you’ll end up with a spider plant with a more developed root system but lagging in its foliage development.
Which would you rather? More leaves or more roots?
I prefer the former when it comes to spider plants.
How to Treat Spider Plant Root Rot
Spider plant root rot is something you should never take for granted because of its consequences.
The earlier you detect and act on it, the higher the likelihood of saving the plant.
As such, it is very important to be aware of the potential signs and symptoms of root rot.
That said, once you’ve diagnosed the problem and seen the rotten roots, the next step is to take action.
Check the Soil and Unpot the Plant
The first step when dealing with spider plant root rot is to confirm to make sure that there is root rot.
One thing I always like to check is the soil.
Wet soil often means there a possibility of overwatering and potentially root rot.
If this is the case, take the plant out of its pot and check the roots.
Healthy roots don’t have a smell except for some earthiness. They are also white in color, feel firm to the touch and very pliable.
On the other hand, rotten roots stink!
This will probably be the first thing you notice once you take the plant out of the pot if there is in fact rotten roots.
Also, rotten roots are brown or black in color. They are soft, mushy and easily break or crumble when you touch them.
Prune the Roots and Affected Leaves
Rotten rots are no good. And they don’t function.
So, you want to prune any black, mushy roots. Be careful when you do since you don’t want to cut any healthy roots.
You want to keep as many (all if possible) of the healthy roots.
The more healthy roots the plant has left, the better chance it has of surviving and recovery.
Make sure you disinfect or sanitize your cutting tool before making any cuts. You can use rubbing alcohol or hydrogen peroxide on the blade.
After pruning the rotten roots, take note of how much you’ve removed.
If you’ve taken off more than 1/3 of the plant’s original root system, you’ll also need to prune the corresponding amount of leaves above the soil.
A smaller root system will have a much harder time supporting the original sized plant. So, pruning the plant to even it out with the root system gives the plant a better chance of survival and recover from spider plant root rot.
You can likewise prune the affected leaves.
Many of them will have wilted, become yellow or brown. You’ll want to remove these.
But you can also do this later on.
Check for Any Fungal Problems
Before you repot the spider plant, it is important to make sure what the cause of the root rot was.
There are usually 2 reasons for root rot.
- Suffocation due to overwatering or waterlogging
- Fungal disease
Fungal disease is another by product of overwatering.
When there’s too much moisture, it makes the damp environment very conducive to fungi development. And there are a few different fungal infections that can cause spider plant root rot.
These fungi will eat through the roots.
And after a while, the roots will rot.
In case, this is the cause, you cannot just repot the plant after removing the rotten roots.
That’s because the pathogens will follow along.
And after a while, the repotted spider plant will experience the same fungal root rot.
Therefore, before repotting the plant, it is very important to disinfect the root system, the pot and properly remove all the soil and dispose of it.
All 3 tasks are important.
You can use a hydrogen peroxide or bleach solution to disinfect the root system and pot.
Also, make sure that all the small particles of soil are removed from the roots. Then dispose of all the soil including that from the pot properly.
Don’t let any of these come into contact with your other houseplants.
Repot the Plant
Once you’ve prunes the rotten roots and disinfected the root system, you can now repot the plant using fresh, well-draining soil
Use new soil that’s dry. Don’t water the soil, at least not for a while.
The goal is to allow the spider plant to start recovery.
Adjust Your Watering Schedule
Last but not least, make sure to modify your watering schedule.
You don’t want to the plant to experience root rot again as it likely won’t survive this time due to its weakened state.
Make sure to wait at least a week before you start watering the plant again.
When you do, try to wait until the top half of the soil has dried before adding more water.
You want to keep the soil on the dry side. And always be wary of wet, soggy or mucky soil when you feel the surface.
Propagate the Plant
Unfortunately, even if you follow all the steps to try to save and recover from spider plant root rot, it may not always work.
You’ll be able to tell since after repotting, the plant will keep deteriorating instead of getting better.
If this is the case, your best bet is to propagate the spider plant.
That’s because it is very likely that the plant won’t recover. Instead, it will gradually weaken and eventually die.
I know some growers who will hedge this even earlier.
What I mean by that is while working to save the plant during the steps above (even before repotting the plant), they’ll also be propagating it already.
That way, whatever happens, they have peace of mind that they’ll still have at least a spider plant when it is all done.