Anthuriums have some of the most stunning and vibrant glossy leaves, but it’s not uncommon for them to develop brown spots or for them to turn all brown and dull. Brown leaves on anthuriums are a cause for concern, but don’t worry – with some expert guidance, your plant can bounce back in no time!
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7 Causes of Brown Leaves On Anthuriums
Here are the most common reasons your Anthurium leaves may be turning brown. If you notice only a few brown leaves scattered among healthy ones, there is usually no need to panic. Read below to try to pinpoint exactly why your Anthurium’s leaves are turning brown.
1. Seasonal Change and Plant Age
When the seasons change, anthuriums may experience temperature fluctuations or a shift in humidity levels that can stress the plant and lead to browning. Winter months often mean drier air inside our homes which can cause problems with maintaining adequate moisture levels in our plants’ soil.
This cause can be pinpointed if you’re in the middle of a changing season, but also if you notice browning on the leaves around the edges more than the middle of the leaves.
It’s important to keep an eye on your anthurium during these times and adjust the plant’s care accordingly. You may need to increase watering frequency or add a humidifier nearby to help combat dry air.
As plants grow older, it’s natural for them to shed some of their lower, older leaves. This is a natural part of every plant’s life, and is not typically anything to worry about. Age will typically make the whole leaf turn brown around the same time.
2. Over Exposure to Direct Sunlight
Overexposure to direct sunlight is a common cause of brown leaves on anthuriums. While these tropical plants can tolerate some amount of sunlight, too much exposure can lead to sunburn and leaf scorching. You’ll know that this is the cause if you notice spots that look burnt on your leaves.
Prevention is easier than nursing an Anthurium back to health, so to prevent overexposure to direct sunlight, it’s important to find the right balance between light and shade. Anthuriums prefer bright but indirect light, so place them near a window with sheer curtains or in a partially shaded area outside.
If you notice that your anthurium’s leaves are turning brown from too much sun, move the plant to a shadier spot as soon as possible, preferably out of any direct sunlight until the plant has recovered. Always avoid exposing it to direct sunlight during the hottest part of the day, as this is a quick way to burn your plant’s leaves.
As long as the leaves don’t begin to rot, you can leave the burnt leaves on the plant if you don’t mind the look. It typically won’t hurt the plant to leave the burnt foliage on, but many people choose to prune away the brown leaves, as they will never turn back to green. When doing this, make sure to use clean, disinfected pruning shears.
3. Low Humidity
Low humidity is another common cause of brown leaves on anthuriums. An environment with low humidity levels can stress out the plant and lead to dryness, which results in brown, crispy leaves. This issue usually arises during the winter months when heaters are turned on to keep homes warm. The hot air from the heater dries out the air inside your home or office and affects your indoor plants’ growth.
You’ll know this is the culprit behind your plant’s brown leaves if they feel crunchy when you touch the brown spot, and if the brown seems to be outlining the leaves.
To prevent this problem, consider investing in a humidifier that will help you maintain a suitable level of moisture around your anthuriums. Alternatively, you can place a humidity tray filled with pebbles and water underneath your plant’s pot to create some extra humidity.
Another effective technique for maintaining proper humidity levels is grouping several plants together as they release moisture through transpiration. This process increases relative humidity around them naturally.
4. Watering Issues
Watering issues can also cause brown leaves on anthuriums. Overwatering and underwatering are the two watering problems that can lead to this issue, but there could also be harmful things in your water that may be causing the brown leaves as well. Use purified water for sensitive plants, or allow any chlorine to evaporate from your tap water before giving it to your plants.
Overwatering and Root Rot
Overwatering is one of the most common causes of brown leaves on anthuriums. It happens when the plant receives too much water and is allowed to sit in that water, without allowing the roots to absorb enough oxygen. This will eventually rot the roots. Root rot can harm your plant, hinder its growth, and ultimately may even kill your plant.
The earliest sign you’ll see when overwatering has occurred is drooping leaves, followed by browning of the leaves. When overwatering is the cause, the leaves will still feel soft, almost mushy. Another sign of overwatering is if there is a smell coming from the soil.
When overwatering occurs, it’s important to take quick action to save your plant. You’ll want to remove the entire plant from the pot, get the soil away from the roots carefully, and thoroughly inspect the roots. Using clean pruning shears, prune away any brown and soft roots. Those have been rotted and will not come back to life. Treat with our Root Supplement.
Avoid overwatering by checking if the top layer of soil feels dry before giving more water, preferably using a moisture meter. Adjust watering frequency depending on environmental factors like light intensity and humidity levels.
Dehydration Caused by Underwatering
Dehydration is one of the most common reasons for brown leaves on anthuriums. Anthuriums require a consistent supply of water to thrive, and without it, they can quickly become dehydrated.
One way to check if your anthurium is dehydrated is to feel the soil. If it feels dry or almost powdery to the touch, then chances are your plant needs watering. However, be careful not to overwater as this can also lead to issues such as root rot, as we covered above.
Another way to determine if underwatering is causing the browning of your Anthurium’s leaves is to feel the leaves that are affected. If they are crunchy, and the brown is affecting most of the leaf, then it’s likely due to underwatering. Don’t worry, though! Anthuriums are fairly tough and will bounce back once you get them rehydrated.
Rehydrating your plant is not always as simple as just giving it a good watering. Sometimes, when a soil becomes really dry, it actually repels water, and will make all the water run off the sides of the pot and drain out the bottom. This gives you the illusion that you’re watering enough, because you see water coming out of the drainage holes. A better way to gauge how much to water your plant is by sticking a moisture meter (or your finger) in the soil. If it’s bone dry, you’ll need to take extra measures to rehydrate it.
To do this, I found it easiest to fill a large bowl or sink with 4-6 inches of water, and then lay the pot (if it’s small enough) on its side inside the water. Let it soak there for about 5 minutes, and then turn it so a different side of the pot is resting in the water. About a quarter turn each time works great, and let the plant soak, turning it every few minutes, for at least 20 minutes.
This method will allow your plant to get hydrated quickly, and will also allow your soil to soak up enough to thoroughly rehydrate also. Check the soil thoroughly for moisture throughout by using a houseplant shovel or rake to dig into the soil carefully and seeing whether the soil in the middle of the pot is moist or dry, and if it’s moist throughout, you can take the plant out of the water and let the excess drain away.
As long as the soil doesn’t dry out completely again, you should be able to water the plant like normal from here.
5. Over Fertilizing
While it is true that fertilizer provides the necessary nutrients to keep your anthuriums healthy and vibrant, over-fertilizing can lead to the demise of your plant. One of the first symptoms of over fertilizing is brown leaves. When you apply too much fertilizer, it can actually burn the roots and prevent them from getting any nutrients or even water.
To determine if the cause of your plant’s brown leaves is over fertilization, see if the brown leaves are droopy. They will typically not be too dried out, either. If you’ve recently applied fertilizer to your plant in the past week or so, and then start noticing brown spots or entire leaves browning, it’s likely that the cause is over-fertilization, and you’ll want to fix the problem quickly.
To prevent over fertilizing your anthuriums, make sure you follow instructions on how often and how much fertilizer should be used. It’s best practice not just for Anthurium but all plants if you dilute fertilizers by half strength before applying them until you know that your plant can handle the type of fertilizer you have for it.
One sure-fire way to prevent over fertilizing is by only giving your Anthurium a plant food that is made for indoor plants. This plant food is given each time you water your plant, and has the perfect balance of nutrients that your plant will be able to absorb quickly, completely avoiding the possibility of fertilizer burn (if administered properly).
To save a plant that has been given too much fertilizer, you’ll want to completely drown the roots. Take the plant outside and let the water hose run through the soil for several minutes. The goal is to wash away any more nutrients that may continue to harm your plant. In most cases, plants will begin to bounce back from this within a few days.
After a plant has suffered from fertilizer burn, they will be much more sensitive to fertilizer for several months, and should not be fertilized again for at least a couple of months. After this, dilute your fertilizer by ¼ for the next six months or so, and slowly increase again to the full recommended amount.
6. Environmental Fluctuations
Anthuriums are sensitive to environmental fluctuations, which can cause brown leaves. These plants prefer consistent temperatures between 60-85°F, so sudden changes in temperature can stress them out. If you’ve recently moved your Anthurium to a new location with different lighting conditions or temperatures, give it time to adjust. Gradually acclimate your plant by exposing it to the new environment for short periods each day until it becomes accustomed.
Drafty windows and doors or air vents can also cause damage to your Anthurium’s foliage. To prevent this, ensure that they’re located away from any draft sources and keep a consistent temperature in their immediate surroundings.
To determine if this is the cause behind your plant’s leaves turning brown, you’ll need to figuratively put yourself in your plant’s place. Environmental fluctuations can cause an entire leaf to turn brown, or it can cause brown spots, so the only way to determine if this is the cause is by knowing how, when, and how quickly your plant’s environment has changed.
Ultimately, as long as the new environment is conducive to your Anthurium’s tolerable range, it will simply take time for your plant to bounce back. Just make sure that the temperature around your plant is within the acceptable range, and that the humidity remains between 50-70%. If the new environment is not within the tolerable range, then you will need to adjust the environment, or move your plant somewhere that it can get what it needs in temperature and humidity.
7. Pests and Diseases
Pests and diseases can also be the culprit behind brown leaves on your Anthurium. These plants are known to attract pests like spider mites, mealybugs, scale insects, and aphids. When these insects feed on the plant’s sap, they cause damage to its leaves leading them to turn brown.
Diseases such as bacterial blight or fungal infections can also cause your anthurium’s leaves to turn brown. Overwatering or leaving water drops on foliage can lead to bacterial infection while fungal problems arise due to high humidity levels or poor air circulation.
To prevent pest infestation, avoid placing your anthurium in areas where other infected plants are present. Regularly inspect your plant for signs of infestation and use organic pesticides if necessary. Keeping a close eye on all your plants will be the best defense against an infestation, as it’s almost nearly impossible to see when one or two of these little guys try to make your plant their home.
For disease prevention, ensure proper watering techniques by allowing soil to dry between waterings, and always make sure that the pot has sufficient drainage holes. Proper ventilation is another way of preventing fungal growth which leads to diseases in these beautiful tropical plants. A fungicide or bactericide treatment may be necessary for some common problems like rust fungus and bacterial blight.
Removing Brown Leaves On Anthuriums
Removing brown leaves on your Anthurium is not always required, unless the problem is a pest or disease infestation. Removing them is mostly for aesthetics, and to signal to the plant to focus more energy on new growth instead of keeping the half-green-half-brown leaf alive.
To remove the brown leaves, it’s a fairly straightforward process. All you need is sharp, clean pruning shears.
First, inspect the leaf that has turned brown. If more than 50% of the leaf has been affected, you’ll want to remove the entire leaf. Cut the leaf stem as close to the base as you can without harming the stem, and without touching the affected part of the leaf to the stem. If there is fungi or bacteria present, you don’t want it to get on the main stem of your plant.
If only a small part of the leaf has turned brown, and it wasn’t caused by a fungus or bacterial infection, you can just cut off the brown part of the leaf, leaving the green part intact. This method isn’t always recommended, but for plants without much foliage in the first place, this is the best option. Take note though, the edge where you’ve cut off the leaf may brown up, almost like a scab on a wound. This brown will not go away, but it’s less unsightly than a whole section of your leaf being brown.
Regardless of what caused the brown leaves on your Anthurium, proper care and maintenance of your plant will ensure it returns to health, and removing damaged parts of the plant will help it get there faster.
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