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Most plant owners will at one point experience root rot – be that orchid or your favorite ZZ plant. If you catch signs of root rot early, you may be able to save your ZZ plant from impending doom.
Overwatering, lack of drainage, and wrong potting mix is the primary reason for root rot in ZZ plants. You can save your ZZ plant from root rot by taking the plant out of its container, trimming away rotten roots, and repotting it in new soil and a pot with drainage holes.
If you are worried about your ZZ plant’s root health or you suspect it has root rot, this post will detail all possible reasons it may have root rot and how to fix it.
Owning a ZZ plant is an absolute pleasure – these plants are low-light tolerant and can survive weeks without water.
With that said, it is easy to cause root rot in ZZ plants because they will only show signs of distress when it’s too late to save them due to their hardy nature.
So, let’s look at some of the most common signs your ZZ plant will show you if it is experiencing root rot and how you can remedy each of these:
One of the telltale signs of ZZ plant root rot is black roots and mushy stems.
If the roots of the ZZ plant are damaged, you will see it start to affect the plant’s stem.
Usually, a rotting root will show about one inch above the soil. These stems will be soft and slimy. If you move the plant, the stem will easily detach, leaving behind the roots in the soil.
Mushy stems are an extreme case, and you should be able to notice other signs of root rot before the stem rots.
A surefire way to check for root rot is to check the roots themselves.
You can do this by gently loosening the soil and gauging the appearance of the ZZ plant’s roots.
The roots will look like one of the following:
- A healthy root system will have firm white roots with some brown spots.
- A rotting root system will have brown or black roots that are slimy and soft to the touch.
The severity of the ZZ plant’s root rot will depend on how long the plant has been left to live in overwatered conditions.
As the roots are left to rot, the plant will show more severe signs of blackened roots.
If your ZZ plant’s stems are starting to fall over or droop severely, it is a sign that your plant may be experiencing root rot.
Overwatering the ZZ plant causes waterlogged soil that reduces a root environment where oxygen isn’t readily available, resulting in unhealthy roots.
Some drooping leaves are completely normal if you have a large ZZ plant (it’s likely caused by the weight of the stem and leaves). You should start worrying if the plant looks like it’s wilting.
If you are unsure of whether your ZZ plant is experiencing drooping leaves due to root rot, check the plant’s roots to confirm.
Yellow leaves on ZZ Plants most commonly occur due to overwatering.
The yellowing (and sometimes browning) tend to occur on lower and older leaves first.
It is also likely to be one of the many signs your ZZ plant is showing you that it’s unhappy. Other signs may include lack of growth, drooping stems, and wrinkled leaves.
Yellowing leaves can also occur due to excess sunlight, bugs, acclimation problems, or temperature stress.
Consider the following things when you’re trying to figure out why your ZZ plant is showing signs of yellow leaves:
- If the soil is waterlogged, overwatering may cause yellowing leaves.
- Brown leaf tips (especially on younger leaves), drooping stems, wrinkled leaves, and odors indicate rotting roots.
- If your ZZ plant is in direct sunlight, the leaves will scorch and turn yellow/brown.
- Irregular yellow spots are often signs of pests or bugs. The bugs feed on the foliage of the plant.
- If you’ve recently purchased a ZZ plant or moved houses, they often need to acclimate to the new environment. As a result, the ZZ plant can develop some yellow leaves when adjusting to its new home.
These problems all require their own diagnosis and solution. If you follow this blog post, you’ll definitely be on the right track to caring for your new ZZ plant.
Like all the abovementioned problems, brown tips are most likely due to overwatering.
If your ZZ plant’s leaves are turning brown, it may also be a result of:
- Underwatering – while most ZZ plants thrive with less water, leaving them without one of their main life sources for prolonged periods may result in drying up and browning.
- Excessive heat and light – ZZ plants do not like to be in direct sunlight. By placing them somewhere with excessive light, the water will evaporate too quickly, resulting in browning leaves.
- Overfertilizing – too much fertilizer can cause the ZZ plant to show signs of fertilizer scorching.
- Extremely low humidity – while ZZ plants don’t require excessively humid environments, they will likely attain brown tips if they are in a moisture-lacking environment.
- Warm and cool drafts – make sure your ZZ plant is placed somewhere where it won’t be subject to hot or cool drafts; it may otherwise experience some distress resulting in browning leaf tips.
The ZZ plant’s leaf tips are the most sensitive part of the plant and easily show signs of distress. Avoid this by placing the plant in an environment suited to its needs and ensuring that you follow a proper watering schedule.
If your ZZ plant’s leaves are curling, it is most likely due to underwatering the plant.
The leaves curl to conserve water and reduce the exposed surface area to reduce water loss.
Curling leaves are also commonly accompanied by browning leaf tips and limp stems.
You definitely want to take some time to figure out if your ZZ plant is receiving too much or too little water and take corrective measures from there.
Here are some other things to keep an eye out for when determining the cause of curling leaves:
- Incorrect lighting conditions – direct sunlight will cause the water to evaporate from the plant too quickly.
- Mushy or dry soil – under and overwatering are the main problems in treating your ZZ plant. If you’re underwatering your plant, the soil will be extremely dry and requires you to water the plant, whereas overwatering will require you to cut back on watering.
- Dry air – your ZZ plant’s leaves may also curl in extremely arid conditions. To remedy this, place it close to other plants or use a tool to increase the humidity around the plant.
- Bugs and pests – as with yellowing leaves, bugs and pests can also cause your ZZ plant’s leaves to curl. If you notice any critters on your plant, isolate them and remove the pest.
Always keep keep a lookout for signs of curling leaves and treat itaccording to the determined cause.
The main cause of moldy and stinky soil is, you guessed it, overwatering!
Waterlogged soil is sticky, slimy and makes for a root rot conducive environment.
You want to water your ZZ plant only when the top layers of soil are dry and allow the soil to dry out entirely before watering again.
You may also have moldy and stinky soil if your plant pot does not have drainage holes.
The drainage holes allow water to flow out and easily help air enter the soil. If your pot does not have adequate drainage, the soil risks becoming breeding grounds for mold and bugs.
If you notice signs of mold or fungus growing in your ZZ plant’s pot, you definitely want to repot it into a sterile pot and give it some fresh soil.
You also want to ensure that the pot has adequate drainage holes to allow water to flow through, rather than build up if you repot it.
Root rot is one of the reasons your ZZ plant may live a shorter life than you intended for it.
The roots are essential for channeling water and nutrients to the rest of the plant, so if this system isn’t fully functional, the rest of the plant will die too.
Let’s see how you can save your ZZ plant if it has signs of root rot:
Knowing the damage caused by the root rot will only be uncovered once you remove the ZZ plant’s pot cover and see the situation for yourself.
If you notice signs of rotting ZZ plant roots, it is best to remove the rotten part and repot it.
Here’s how you can go about repotting your ZZ plant:
- Remove the ZZ plant from its pot gently to avoid losing healthy roots – you may want to press the pot between your palms to loosen the soil if the plant is rootbound.
- Once removed, run the plant’s roots under a stream of water in your shower or bath to wash away any excess soil.
- Examine the now clean roots and identify rotten roots – these will be brown or black and extremely mushy to the touch. You probably have a few rotten roots to remove from the ZZ plant if the plant smells bad.
- Using clean scissors or a knife, remove the rotten portions of the plant. When cutting, be sure to cut at least an inch up from the site of rot – this way, you’ll prevent the root rot once you’ve repotted the plant.
- Be sure to properly discard the rotten roots to avoid adding them back into the new soil.
- You can take an additional measure by using fungicides on the roots to prevent pathogens in the future. Fungicides are formulated to target specific pathogens, so be sure to buy one suitable for your needs and follow package instructions when applying.
- Using a sterilized pot and soil, repot the ZZ plant into the new container. You want to use well-aerated soil but will still retain moisture – this type of soil will generally consist of potting mix and peat moss, bark, or perlite.
- Water the now transplanted ZZ plant – you want to ensure that the soil drains properly to reduce root rot and unnecessary stress on the plant. Do not overwater the plant and allow it to dry out between waterings.
Following these steps will ensure that your rotting ZZ plant makes a full recovery.
Repotting your ZZ plant can stress out the plant quite a bit – and with the existing root problem, it is a whole lot worse.
To minimize the ZZ plant’s shock, you want to do the following:
- Place the ZZ plant in a spot where it will receive light but no direct light – you can progressively move the plant closer to the light source once it’s re-established itself.
- Do not forget to water the ZZ plant, but also don’t overwater it – if the top layer of the soil is dry, be sure to give it water and allow the water to drain out properly.
Because the ZZ plant’s roots are damaged, they’ll need some time to acclimate to their environment to properly channel the nutrients and water to the rest of the plant.
If you see that your ZZ plant still isn’t showing any signs of improvement after 1-2 weeks, you may want to consider taking the following measures to ensure you don’t lose it completely:
If you notice that your ZZ plant has little chance of survival based on how many intact roots are there, you want to start preparing to lose the plant.
Fortunately, there are simple ways you can increase how many ZZ plants you have while saving them from their imminent death.
Here is how you can propagate a ZZ plant:
The fastest and most reliable way of propagating a ZZ plant is through stem cutting.
Here are the steps to propagate your ZZ plant through stem cutting.
- Find a viable piece of the plant to take a cutting from – you don’t want any signs of rot to show on the piece you want to propagate.
- Use a sharp knife and cut the ZZ plant at the base of the stem (or as high up as needed for no rot).
- Make as many cuttings of the plant as you need – if the plant is rotting, you ideally only want to leave a few stems on the main plant and propagate the remainder.
- Place the cuttings in a container with clean water, ensuring that only the cut part is submerged in water.
- Change out the container’s water every 3-4 weeks and keep a close eye on algae growth or signs of rot.
- If you have a rotting cutting, remove it from the water and discard it immediately.
- Keep the container with cuttings close to a window that receives loads of light but no direct sunlight.
- When your cutting has successfully rooted (at least 1-inch of roots), you can transfer it to a pot with moisture-retaining, well-draining soil.
Repotting the plant is simple.
You want to ensure you repot it in a container with ample drainage holes and good quality soil.
Place the cuttings 2-inches into the potting soil (so 1-inch of root and 1-inch of the plant’s stem) – this allows the plant to remain stable.
Gently press the soil to secure the plant and ensure all your soil doesn’t drain out when watering it for the first time.
You can put multiple ZZ plant stems in the same pot to make it look more like the original plant you lost to root rot.
Remember not to fill the new pot to the rim and water the ZZ plant cuttings thoroughly.
Unlike stem cuttings, ZZ leaf cuttings will take longer to develop roots and, subsequently, rhizomes.
It is still very possible to propagate your ZZ Plant with a leaf cutting through the following steps:
- Start by cutting the leaf of the ZZ plant as close to the stalk as possible, leaving a bit of the stem on the cutting.
- Place the ZZ plant leaf cutting about 1cm deep into a pot filled with soil.
- Water thoroughly once placed in the soil and do so about every two weeks when the soil has dried out.
- Place the propagating leaves in an area that receives a lot of light but no direct sunlight.
To increase the success of your propagation efforts, you want to take multiple ZZ leaf cuttings.
A successful propagation will show growth after 3-4 months, depending on when you made the cutting – cuttings will generally propagate faster in summer months than winter months.
The main cause of root rot in ZZ plants is overwatering.
Because ZZ plants have rhizome root systems, they can store and access water long after the soil has dried out.
Here’s how you can ensure that you give your ZZ plant just enough water to keep it happy:
As a responsible plant parent, you have probably developed some kind of watering schedule to make sure you keep everything alive.
The only problem with that is that you don’t have to water your ZZ plant as frequently as you do a Peace Lily, for example.
Instead of watering your ZZ plant on a schedule, use a soil moisture meter instead, and only water your ZZ plant a few days after it’s hit the “dry” zone.
If you don’t want to buy a moisture meter, stick your finger into the soil:
- If the soil is dried out completely, give it water.
- If there’s still moisture, hold back on watering it for a few more days.
You also want to adjust how much water you give the plant-based on the temperature.
During cooler months, you want to cut back on watering in the cooler months as the water evaporates at a slower rate and increase the watering frequency during warmer months when the water is prone to faster evaporation.
The ZZ plant doesn’t lose water that quickly, so if you continue to water your plant when it doesn’t need it, it runs the risk of developing root rot.
To avoid developing a shallow rhizome system in your ZZ plant, you want to ensure that you water it deeply.
Deep watering will ensure that the roots of the ZZ plant grow deep into the soil, resulting in a more stable plant.
A super crucial part of watering any plant is to check that you’ve removed any source of excess water – be that throwing the water out of your cover pot or water tray.
ZZ plants can easily develop root rot if it’s overwatered or can’t drain water properly.
If your ZZ plant has root rot, you want to identify the reason for the rotting roots and address it accordingly.
You’ll most likely need to repot your ZZ plant and, in extreme cases, start propagating it to keep it alive after the mother plant has died off.
Fortunately, the ZZ plant is one of the hardiest on the indoor plant market, and you will likely be able to save it from any rotting root situation if you follow the right steps!