Dieffenbachias might be toxic, but they’re still one of the most common houseplants in the world. They’re easy to find, easy to maintain, and come in various sizes ranging from three to six feet in height—even eight feet in some cases!
But despite their easy-going nature, they’re still susceptible to one of the number one killers of houseplants—root rot.
You might not realize it, but dieffenbachias are particularly vulnerable to root rot, especially when they’re kept indoors. To learn more about how you can diagnose and treat root rot if it occurs, and prevent it in the future, continue reading.
What Is Dieffenbachia?
If you have never heard of dieffenbachias before, the chances are that you have still probably seen them. They’re one of the most common types of houseplants interior designers use for decoration because they’re low maintenance and don’t require direct sunlight.
Dieffenbachias are also called “Dumb Cane” and “Leopard Lilly.” They feature long green leaves with white spots that get larger when they require more sunlight. They also have unmistakably unique flowers that look like white tubes more so than your typical flower.
The flowers are made up of two parts—a spathe and a spadix. The spathe is green and looks like a leaf opening up, as the spadix emerges from it appearing like a small white finger.
Every dieffenbachia is toxic, however, so you need to be careful when handling it, which will be covered later in this article.
Can You Overwater a Plant?
All plants need water to survive, but just like anything else, too much of a good thing can become bad. Every plant is different. Some draw moisture from the air and don’t require direct watering, while others wilt if their soil is not kept moist enough.
Dieffenbachias fall somewhere in between, which is one reason why they’re so popular. You only need to water your dieffenbachias once or twice a week, depending on their size and the time of year.
During the winter months, the reduction in sunlight forces them into a state of dormancy, so watering can be reduced. Once the spring season arrives though, it’s necessary to water consistently once or twice per week.
You need to be careful though, plants in the ground outside can often handle lots of rain, as they drain well, and have plenty of other plants around to absorb excess moisture—not to mention the combination of sun and wind for airing things out.
What Happens If I Overwater My Plant?
The biggest and most common problem new plant enthusiasts run into when growing new potted plants is overwatering.
When you see discoloration or yellowing and shriveling of leaves, it’s almost a human instinct to want to give the plant something to drink to help the problem. The actual problem though, is that you’re giving it a drink too often.
When a plant gets too much water, it will absorb it, often to the point of the cell walls in the leaves bursting, resulting in lots of little yellow spots. If you see this, stop watering, and don’t water again until the soil is completely dry.
Watering a potted plant too much can cause a buildup of moisture if that moisture has nowhere to go or if your plant can’t use it.
Does Dieffenbachia Need Drainage?
Dieffenbachia is a plant native to tropical climates, which means that it needs a good level of moisture to thrive. However, it’s not a swamp plant, so it still needs some drainage.
Dieffenbachias need drainage holes in whatever pot you keep them in, as well as a soil mixture that allows for both water retention and water runoff. A good soil mixture for dieffenbachias is something such as equal parts peat and perlite.
The peat will help retain moisture, while the perlite acts as a buffer, allowing air to flow through the soil and forcing water to drain through. If your soil doesn’t drain well enough, it’s possible that you may encounter root rot.
What Is Root Rot?
Root rot is exactly what it sounds like—rotting roots. Essentially, root rot is a plant disease in which the roots of the plant begin to decay while the rest of the plant is still alive. You can probably imagine why it’s important to avoid it.
Root rot occurs when the roots of a plant remain in wet soil for too long. Microbes and fungi begin to take over, and decomposition begins at the roots. The leaves and foliage of the visible plant will also begin to die, but there’s often still hope for saving the plant if it’s caught early.
Root rot can occur in two common ways. If the soil is too wet from overwatering and kept in a cold environment (below 60 degrees Fahrenheit), it’s likely that root rot will begin to set in.
On the other hand, if watering is normal, but the environment is overly humid, root rot may still occur. In either case, the soil needs to be dried out immediately, or changed completely, as you’ll see later.
How to Tell If Your Dieffenbachia Has Root Rot
There are several common indicators of root rot. The first step in saving your dieffenbachia is by recognizing it as soon as possible—the sooner the better!
If your dieffenbachia is yellowing and shriveling, it’s possible that you’re just watering it too much and are on the way to root rot. If this is the case, stop watering, and monitor the plant regularly until the soil has dried out completely.
Another tell-tale sign of root rot is the moisture level of the soil. If it stays moist for more than a few days, there’s a good chance that the roots have stopped absorbing water and are instead beginning to decay. As soon as you notice this, check the smell of the soil.
If it smells foul, sour, or like fish, there’s a high probability that you have a plant with rotting roots. A foul odor indicates fungi or bacteria growing in the soil, which needs to be addressed as soon as possible.
How to Save Your Dieffenbachia From Root Rot
Dieffenbachia roots experience root rot when they are exposed to a lot of water, especially during periods of heavy rainfall or overwatering, as already mentioned.
These types of plants don’t grow well if the soil is constantly wet and hot, or wet and cold, so it’s important to plant them in pots or in the ground with good drainage. Root rot is a disease that affects the roots of the plant and also can cause leaves to yellow and wilt, which is how this condition is commonly known.
If you have noticed that your dieffenbachia is rotting at the roots, it’s likely still possible to save it. By following these steps, you’ll be able to get rid of the root rot, save the plant, and prevent root rot from occurring again in the future.
Gather the Necessary Tools
Treating root rot is a delicate procedure that requires specific tools. It might seem daunting at first if it’s your first time repotting a plant, but it’s easy enough for just about anyone to do. Before you begin, make sure that you have all the necessary tools.
You’re going to need pruning shears or very sharp scissors. Make sure they’re very sharp, as you want to make as clean of a cut as possible to promote efficient healing.
Also, just like in humans, plants are susceptible to infections when they’re injured, so a clean cut ensures faster healing and less chance of becoming infected and slowing healthy growth.
As you know, dieffenbachias are toxic. Even just touching them with your bare hands can cause irritation and rash, so it’s important to wear gardening gloves, or two pairs of surgical gloves to protect your hands.
When treating root rot, you need to keep in mind that you’re dealing with microscopic bacteria and fungi that can spread easily just by touching it.
Because of this, you’re going to need a disinfectant such as hydrogen peroxide, which is perfectly safe to use directly on the roots if diluted with water. You can also use it to disinfect the pot later on.
You will also need a clean cloth for wiping, a basic soap without scent or additives for the pot, and finally, a fresh mixture of soil.
Remove From Pot
You can smell the soil and observe the yellowing of the leaves, but until you remove the plant from its soil and get a good look at the roots, you’ll never know for certain if root rot is the issue.
So once you have all of the necessary materials gathered, pull your dieffenbachia carefully from the soil and dust off all excess soil from the roots with your hands to get a better look.
Healthy roots will appear white and feel firm and springy. Rotting roots will be brown or reddish brown and will feel soft—like rotten vegetation.
Remove Rotting Parts
Attention to detail is vital when physically removing the root rot. Before you begin, use your cloth and disinfectant to clean the scissors. Cut away anything that is visibly rotten or smells rotten. If it’s questionable, cut it off.
It’s essential that you disinfect your scissors in between each cut, as failing to do so will only result in spreading the root rot further throughout the root system.
If necessary, it’s possible for dieffenbachia to regrow without any roots. You just need to learn the process of propagation.
Trim Affected Foliage
The process of trimming affected foliage should be treated exactly the same. Make sure you clean your scissors and surgical gloves in between each cut because not doing so can spread the fungus even further.
Cutting affected leaves and branches from the plant will also help to speed the recovery process along, as the plant will be able to focus growth hormones on new growth rather than attempting to recover old ones.
Disinfect Root System
Once you’ve cut away the remaining bits of rotten roots, the final step in treating your dieffenbachia is disinfecting the root system. To do so, dilute hydrogen peroxide with water, using a solution ratio of 10 to 1. Ten parts water, and one part 35%, additive-free hydrogen peroxide.
You can disinfect the roots using a spray bottle, followed by wiping them with a clean cloth wet with the same solution, or fill a bucket with your disinfecting solution and dip the roots into it several times, finishing by wiping it with a clean cloth.
Disinfect the Pot
Since you don’t want to have the same fungal or bacterial problems you just spent time and energy eradicating, make sure that you sterilize your pot completely before replanting your dieffenbachia.
Start by getting rid of all of the old soil—it still likely has fungi present, so it’s not useful to you at all. Once you’ve gotten rid of the old soil, disinfect the pot.
If you want to completely avoid having fungal problems again in the future with the same plant, you can also get a new pot for a fresh start.
Replant Your Dieffenbachia
Now that you have a sterile pot and plant, take your fresh soil mixture, and use it to fill the pot about a quarter of the way up. Then add your dieffenbachia to the soil, adding the mixture around the sides until its roots are completely covered in soil. Then add water to the soil until you see it begin to drain from the bottom.
Optimize Plant Recovery
Now that you’ve finished eradicating the root rot from your dieffenbachia, it’s time to help it recover from the stress. Make sure that it stays in a warm spot, with plenty of filtered light—no direct sunlight. The more humid, the better, as humidity improves root growth.
Prevent Root Rot in the Future
Make sure not to water too much! Once your plant begins to reset its roots and grow again, you only need to water it once or twice per week. If the soil is still wet after a few days, you need to replace it with a soil that drains better.
Root rot is detrimental to any plant, but that doesn’t mean you can’t help your dieffenbachia survive. Follow these tips and your dieffenbachia will be back to healthy growth in no time.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.