First and foremost, let’s address how difficult that name is. I mean…my mom grew these indoors when I was young but I always called them dumb canes because that was much easier to pronounce than dieffenbachia.
Yeah…we’re calling them dumb canes today or some might even know them as leopard lilies. Either way, it’s the same plant.
If your dumb cane is experiencing yellowing leaves, the first step is to identify the root cause before taking steps to resolve it.
Why Are My Dieffenbachia Leaves Turning Yellow?
5) Improper Lighting
Both too much or too little light can negatively affect your dumb cane. This means that neither a bright windowsill nor a shaded barn is the ideal place for your plant.
The best lighting is stable and not harsh. Keeping your plant outdoors under the hot sun will scorch its leaves, whereas inadequate light will make leaves weak, yellow, and droopy. Indirect light, ideally coming in from thin curtains, can work very well for dumb canes.
4) Extreme Temperatures
Dumb canes are plants that can thrive indoors. However, if you keep too close to heaters and air conditioners, the temperature extremes they experience will likely stress them out, leading to leaf yellowing and possibly even shedding.
Try to avoid moving your plant indoors or outdoors too frequently, and be mindful of sudden temperature changes. Both extreme heat and cold can stress your plant, increasing the risk of discoloration.
3) Nutrient Deficiency
A nutrient deficiency is a common culprit behind yellowing for many dumb cane growers. Since many people cultivate these plants indoors using garden soil and dirt, the growing medium often lacks the essential nutrients needed for optimal growth.
First, instead of using basic garden soil for growing your dumb canes, opt for a high-quality potting soil mix. You can use a balanced fertilizer that’s especially high in nitrogen to reverse yellowing and restore healthier leaves.
2) Pest Damage
When I was young, the dumb canes my mom grew were attacked by pests because she kept most of them outdoors. The leaves had unusual holes and bite marks, clearly showing that the tiny garden monsters were responsible for the damage.
Now, what should one do about a pest infestation? Well, try to drive pests away from your dumb cane using pesticides. They’re easily available at most basic gardening stores. But, if you’re looking for a natural option, just add 1-2 tablespoons of neem oil to a gallon of water and you’ll have a homemade pesticide solution.
1) Overwatering
Although dumb canes prefer consistent moisture, watering them too much or too often can lead to overwatering issues like root rot and leaf yellowing. Though you can’t do much about your soggy plant right away, avoiding going overboard with the water in the future is your best bet.
As a good rule of thumb: water your dumb cane when the first inch or two of the soil feels dry to the touch. But, if it’s still sufficiently moist then hold your horses!
Should I Cut Yellow Leaves On Dieffenbachia?
This is a tricky one and it all depends on the condition of those yellow leaves.
If they’re brittle and loose enough to pull off by hand, by all means, remove them. At that point, they’re just a waste of energy for your plant.
However, most people make the mistake of thinking the plant has no use for yellow leaves. But, more often than not, your dumb cane is still taking the remaining energy from them. So, just keep that in mind when deciding whether to cut the leaves off or not.
Final Words
Dumb cane leaves fortunately do not turn yellow for dumb reasons. There’s definitely something you’re overlooking or not providing enough of that’s causing the plant to become stressed and experience leaf discoloration.
Reflect on your plant’s care routine to identify the issue and you’ll be well on your way to resolving it quickly.
