If your anthurium leaves are curling then it is going through a stress condition. I’m going to take you through the most common causes and some less common potential issues too.
The common cause of anthurium leaves curling is a lack of water. This could be due to underwatering or low humidity in the air around the plant. Besides, temperature stress, diseases, and insect infestation can also cause leaves curling issues. Either way, the effect is similar – curling leaves that quickly turn dry and brown before dropping off the plant.
We’ll also explore solutions to help you get your Anthurium’s leaves back to their astonishing best.
If you don’t water your Anthurium enough, it will quickly let you know. The leaves will droop and then curl, then turn brown and drop off the plant.
This happens because when there isn’t enough water to keep the cells of the leaves hydrated, they begin to collapse, causing the leaf to curl.
This helps the plant avoid losing even more moisture through its leaves as the exposed surface area is smaller.
Water your Anthurium plant regularly, and check the moisture level of the potting mix every day. How often to water depends on the conditions.
In hot weather, you might need to water your plant every couple of days. In cooler weather, once a week or less should be adequate.
Make sure to water your plant only when it needs it. Use your finger to check the top inch or two of potting mix – if it’s dry, give your plant a drink.
Another way to check is to pick the pot up – if it feels light, the plant probably needs some water. You can also use a moisture meter to keep track of the moisture level of the potting mix.
To help your plant maintain a healthy root system and to discourage diseases, water it from below by placing the pot in a tray of water for an hour or so. Never leave it standing in water for too long as waterlogged soil encourages root rot.
Anthuriums are tropical plants native to the rainforests of South America. They need a humid environment to thrive and will quickly show symptoms of dehydration if placed in a position without enough humidity.
If the leaves of your plant are dry, curled, and turning brown from the edges, this could be the issue. Low humidity causes a plant to lose water through its leaves (a process called transpiration) much faster than it usually would.
The plant can’t replace this water quickly enough, and the cells begin to collapse. Low humidity can kill a plant in a few days, so it’s essential to tackle it straight away if you suspect this problem.
Make sure that the humidity level around your plant is around 70-80%. The average home has a humidity level of about 45%, so you’ll probably need to significantly increase the humidity in your home to keep this plant happy.
There are a couple of options to achieve this – buy an electric humidifier, or place your plants on humidity trays.
These are trays of water underneath the plant, with pebbles to keep the plant out of the water. Alternatively, you could keep your plant in the most humid part of your home – usually the bathroom.
Root rot from overwatering
If you’ve been giving your Anthurium lots of water, but it still looks dehydrated, with curling, dry leaves, it could be that you’ve overwatered and triggered root rot.
Root rot is a killer for all houseplants and is especially dangerous because the symptoms make it look as if the plant needs more water when more water only makes the problem worse.
Root rot is caused by several types of microscopic fungi that thrive in wet environments, such as waterlogged soil.
The fungus destroys the roots of a plant and stops it from absorbing water and nutrients, leading to cell collapse and drooping curling leaves, and eventually death.
Take care not to overwater your plant. Only water when it needs it – when the top of the potting mix is dry.
Don’t water to a schedule as this is likely to lead to overwatering, and make sure to adjust watering depending on the season and conditions.
Good drainage is essential to prevent root rot, so make sure that the plant’s pot has plenty of drainage holes in the bottom.
Too much Direct Sunlight or Lack of Light
Anthuriums don’t like a lot of direct sunlight on their leaves. They are adapted to the shade of the rainforest and are susceptible to sunburn if exposed to harsh sunlight.
If you’ve been keeping your plant on a sunny window or similar situation and its leaves have started to curl or turn brown, this is likely to be the issue.
Although Anthuriums don’t like direct sunlight on their leaves, they do require quite a lot of light to be happy.
In their natural environment, they receive 8 – 12 hours of daylight per day, so it’s best to try to replicate this.
Lack of sunlight will cause your plant to lean towards the nearest light source, produce few flowers and smaller, slower-growing leaves and flowers.
Eventually, as the plant struggles to make enough food to support itself, leaves will curl up and die off.
Keep your plant out of direct sunlight, but where it gets plenty of bright, indirect light. A position a few feet away from a window will suit the plant well.
Don’t keep your plant in a very dark environment like a windowless room or at the back of shady space.
Instead, aim to give your plant at least 8 hours a day of bright, indirect light. In darker months, consider using grow lights to give your plant a boost.
Anthuriums are used to a tropical climate, where the temperature doesn’t vary much from day to night or season to season.
If you keep your plant in a position where it is subject to fluctuating temperatures, such as by a drafty window or near a radiator, the stress could cause its leaves to curl and drop. Very cold water can also cause temperature stress.
Keep your plant in a situation where the temperature is as stable as possible, away from sources of heat or cold.
Anthuriums thrive best in a constant temperature of 65-85°F (18-29°C). Their growth will slow down dramatically if temperatures drop below this for long.
Use lukewarm or room temperature water to water your plant to avoid temperature stressing the roots.
Over or Underfeeding with Fertilizer
As long as they are grown in a rich potting mix, Anthuriums don’t need much feeding at all. Overfeeding these plants is easy to do, so if you’ve fed your plant lately and its leaves are now curling, this could be the problem.
If you’ve had your Anthurium for a long time in the same potting mix and have never fed it, curling leaves could be down to a lack of nutrients. The plant will probably also produce few flowers if this is the issue.
During the growing season, feed your plant every couple of weeks with a half-strength liquid fertilizer rich in phosphorous.
However, if you’ve recently repotted the plant in a rich potting mix, you probably won’t need to feed it for a couple of months.
It’s much easier to overfeed these plants than underfeed them, so if you’re unsure whether your plant needs feeding, it’s best to hold off.
Tap water contains several undesirable substances for Anthuriums, like mineral salts, chlorine, and fluoride. Over time, these can build up in the potting mix and cause problems for the plant.
The minerals build up around the roots of the plants, preventing them from absorbing water and nutrients. They can even burn the roots if they are in a high enough concentration.
Try to give your plant filtered water where possible. Watch out for white or yellow crust forming on the top of your plant’s potting mix – this is a sign of mineral build-up.
If you notice this, repot the plant in fresh potting mix, and if you see any build-up around the roots, gently rinse them in freshwater.
Anthuriums can suffer from several bacterial or fungal diseases, although plants kept inside are less susceptible.
Apart from root rot, these diseases usually cause brown or black patches or blotches on the plant’s leaves, stems, or flowers, which gradually spread. The affected parts may start to curl and die off. (Source: University of Florida)
If your plant is diseased, immediately move it away from other plants to avoid spreading the infection. Remove infected parts from the plant if possible.
For fungal diseases, a fungicide treatment might be effective. However, both fungal and bacterial diseases can be challenging to treat once they have taken hold, so it’s best to avoid them in the first place.
Never reuse infected potting mix or equipment without sterilizing it first. Avoid splashing water onto your plant, as many diseases spread this way.
Water from below if possible. Misting is often recommended to increase humidity, but this is a great way to spread disease, so it’s best avoided.
Anthuriums are usually safe from pests, but infestation is possible. Anthuriums can fall prey to sap-sucking pests like scale or mealybugs, which attach themselves to the stem or leaves of the plant and feed on the sap. As a result, the plant weakens, and leaves might start to curl and die off.
If you see pests on your plant, use a pad soaked in rubbing alcohol to remove them. Keep checking and remove any pests as soon as you notice them.
Spraying the plant with a horticultural soap solution or oil will discourage further infestation.
Anthurium Leaves Curling After Repotting
Repotting is a dangerous time for plants, as it’s easy to damage delicate roots during the process.
When a plant’s roots are damaged, they don’t function properly, and the plant might not be able to take in adequate water or nutrients.
If you’ve recently repotted your plant and its leaves are curling, this could be the issue.
Usually, plants survive repotting stress. It’s best to leave the plant alone and let it recover – make sure that you give it the best care during this time and avoid stressing it further.
The best way to avoid this problem is by repotting your plant only when necessary – every two or three years – and being very careful to avoid damaging the roots when you do.
Curling leaves on an Anthurium are a sign that something is wrong in its environment or with how you are caring for the plant.
Thankfully, these plants are very tough, and you’ll likely be able to solve the problem and save your plant. The most important thing is to understand what’s causing the problem and act quickly.