Anthuriums, also known as flamingo lilies, are showy tropical plants with glossy, heart-shaped, dark green foliage and colorful flowers. With proper care, these plants produce attractive blooms all year round.
Browning anthurium leaves are often due to nutrient deficiency, scorching from direct sunlight, or watering problems. Feeding the plant with a balanced houseplant fertilizer and ensuring its soil is constantly moist and not soggy can help fix the brown leaves.
The good news is that providing proper care for the anthurium by mimicking its native environmental conditions will get it looking happy and healthy again. I’ve explained some practical hacks to stop anthuriums from going brown below.
Why do anthurium leaves turn brown?
First off, browning foliage is a sign something isn’t right. You want to check the plant for pests and diseases before anything else. It could also indicate a thirsty plant.
Let’s dive into the common causes and remedies.
Anthuriums thrive well in a spot with bright indirect light but don’t do well in direct sunlight, which harms the plant and causes the leaves to droop and appear scorched.
Anthuriums prefer bright, indirect sunlight with temperatures between 59°F-85°F. But excess direct sunlight scorches the plants and makes their leaves turn brown at the tips and edges.
To correct this, place your plant 3-4 feet from an east-facing window where it will receive the dappled light it needs. A south or west-facing window is also a good option, but keep an eye on the plant as the afternoon sun can sometimes be too hot.
Note that without the correct exposure to sunlight, anthuriums won’t bloom even if they look healthy.
The humidity is too low
Anthuriums prefer warm, moist conditions with about 70% percent humidity. Brown leaf tips and wilting leaves and flowers are signs of humidity stress. Your indoor air is probably too dry.
“We see this sign quite often in outdoor plants toward the end of the summer months when temperatures are high and humidity low. Leaf edges turn brown, brittle, and dry,” says Sarah Browning, a Nebraska Extension Educator.
The same could be happening to your anthurium.
Low humidity from air conditioning and heating vents often causes anthurium leaves to curl and turn brown at the tips and edges.
Apart from humidity issues, there might be reduced airflow in your house.
Fixing low humidity for anthuriums
Use a humidifier near the affected plants or group the plants together to create a humid microclimate for them. Their transpiration will improve the humidity around them.
Brown anthurium leaves caused by low humidity can be fixed by installing a humidifier in the room with the plants. Check the moisture levels in your house using a hygrometer and maintain healthy ranges for your plant.
Another practical fix for browning anthurium leaves is placing plants in trays with stones and water. You can make one such tray by filling it with 2-3 inches of pebbles and adding water halfway up the stones.
Place the plant on the stones rather than directly in the water to prevent root rot. This will humidify the area around the plant, helping fix the brown foliage.
Also, remember to move your anthuriums away from air conditioning and heating vents.
If you applied too much fertilizer recently, it is possible that the browning is caused by fertilizer burn. Excessive fertilizer saturates the soil with salts, which make the absorption of water and the nutrients themselves difficult.
Fertilizer burn begins as yellow marks on the foliage of the plant. The brown marks appear much like leaf blotches, spots, scorch, or even tip burns. It is easy to confuse these with insect damage or disease.
Note that if your anthurium has brown edges or leaf tips, also called marginal leaf browning, it is likely due to fertilizer burn.
The best fix
Repotting in a fresh potting mix is the most recommended fix for overfertilized anthuriums showing browning leaves. Alternatively, running water through the pot several times to wash away the excess salts can also help the plant recover.
However, you risk waterlogging the soil and causing further problems such as overwatering and root rot.
Keep an eye on the plant and avoid feeding it for 2-4 months until it recovers. Afterwards, feed your plant with half the recommended synthetic fertilizer or use compost or organic fertilizer to nourish it.
I’ve seen instances of rust fungus where houseplants develop small brown spots all over the leaves. These brown spots appear to sit on top of the leaves and can be wiped off. It is very contagious, so even the newest leaves always develop spots. Other plants nearby may also show signs of rust fungus.
Should you determine that rust fungus is the culprit, I recommend cutting off the affected leaves before treating the remaining ones with a copper fungicide.
Copper fungicide is only effective when the fungus still hasn’t penetrated the leaf and stays on the leaves. Thats why it is more of a preventative rather than active treatment.
Overwatering and underwatering
Knowing when to water houseplants is key to keeping them healthy. If your anthurium is droopy with crispy brown areas on the leaves, it is probably underwatered. The soil is dry and the plant is dehydrated.
An additional sign of underwatering is curling leaf tips and edges. Leaves may also dry and drop off if the plant stays unwatered.
Like underwatering, overwatering also causes anthurium leaves to turn brown at the tips and edges. Overwatering leads to soggy or overly wet soils, weakening the roots and decreasing their ability to absorb water.
Adjust the watering frequency. Feel the pot’s weight – an underwatered anthurium has browning leaves starting from the lower parts, and the pot feels light when carried.
Water your plant immediately until water drains out of the holes to ensure the soil is moist enough.
As a rule of thumb, water your anthurium when the top one to two inches of soil is dry. A simple way to find out is by sticking your finger into the soil to check for moisture. If the finger comes up dry, your plant is thirsty.
Check other issues that can dry your soil quickly, including high drainage and small pots, and correct them.
In the case of overwatering and root rot disease…
Repot the plant
Soggy soils from overwatering cause root rot disease. To correct the overwatering problem, check if the plant’s roots are black or brown, smelly, and feeble.
If they are infected, prune the sick roots with sterile pruning shears or scissors and wash off the soil around the remaining good roots. Bring a new pot with fresh, well-draining potting soil and repot your anthurium. Rinse the plant and place it in bright, indirect sunlight.
Anthuriums infested by pests have irregular yellow or brown spots and holes in the leaves. Mites are quite common during the warmer months of the year.
While indoor anthuriums are rarely affected by pests, some insects might crotch the plants from summer bathing or when a new, infested plant is brought in without proper inspection.
The most common pests infesting anthuriums are aphids, spider mites, mealybugs, and thrips. These intruders suck sap and eat the plant’s leaves and stems, leaving brown patches as the veins die.
Get rid of the pests
Hose the plant and treat it with horticultural oil
Carefully examine your anthurium to check for pests. They mostly hide on the undersides of leaves. Remove a couple of pests using your hands. Hose the plant’s leaves, stems, and other parts to eliminate them.
Next, to deal with heavy pest infestation, wipe your plant with a cloth soaked in diluted neem or horticultural oil. The oil has scents that prevent re-infestation.
Bacterial and other fungal diseases
Anthuriums are highly susceptible to fungal and bacterial infections. Since they love warm and humid conditions, some bacterias and fungi take advantage of them, infest the soil, and cause diseases.
The most common bacterial disease affecting anthuriums is leaf blight, caused by Xanthomonas. This bacteria leads to small yellow blisters on the leaf, which spread to the remaining leaves, later turning them brown.
A leaf blight-infected anthurium can spread the disease to nearby plants. Another disease that causes brown leaves in anthuriums is bacterial wilt, caused by Ralstonia solanacearum bacteria.
Fungi such as Pythium and Fusarium also attack anthuriums, resulting in brown spots or irregular patches on the foliages.
Severe fungi and bacteria infestation can lead to irreversible damage, and the plant might eventually die.
Prune the damaged brown leaves
Brown anthurium leaves from bacterial and fungal diseases cannot be saved. Keeping them longer will spread the disease to the other uninfected parts. Prune all the brown sick leaves. If most are brown, you must dispose of your plant.
After pruning the less damaged leaves, adjust the growing conditions to discourage bacteria and fungi from breeding. The soil should be relatively moist and not soggy. Place your plant in indirect sunlight and ensure humidity is 70%.
Will the brown leaves turn green again?
It depends. Small brown areas can turn green again if remedied, but extensively damaged leaves won’t turn green again. Cutting off anthurium leaves with large brown patches is recommended.
Should I cut off brown anthurium leaves?
Cutting brown anthurium leaves is the best way to encourage newer, green ones to develop. By so doing, the plant concentrates most of its energy on growing fresh foliage instead of using it to revitalize the brown leaves. Cut only the small brown leaf parts. A considerable leaf portion should remain for photosynthesis.
Anthurium leaves mostly turn brown because of excess direct sunlight exposure. Underwatering, overwatering, low humidity, cold drafts, and overfeeding can also turn the leaves brown. We recommend fixing the problem immediately and providing ideal growing conditions to save the plant.