Calatheas are a great family of houseplants with incredible leaves. So it’s even more of a shame when we notice that these beautiful leaves are turning brown. Whether it is just the tip or edge of the leaf, or actually the entire leaf, this is an indication that something isn’t ideal in either the care or environment of your plant. This post will help you figure out what the main causes of brown Calathea leaves are, as well as how you can address the issue and prevent them from occurring.
Underwatering often causes brown Calathea leaves
This is the most common cause of brown leaves on a Calathea plant. They don’t like to have super dry soil for weeks and weeks so consistent underwatering will harm your plant.
When underwatered, the leaves on your Calathea will not only turn brown but will be dry to touch and a little limp. If you fear that not enough water is causing the brown leaves then take the plant out of its pot and inspect the soil. If the potting mix is very dry (and almost like powder) then this is definitely the problem.
Your initial thought might be to drown the plant in water immediately to compensate for the lack of it. However, plants get shocked by rapid and sudden changes in their environment. Therefore drowning them in water is actually the wrong this to do. Instead, you want to slowly reintroduce regular watering by giving the plant a little bit once a day for a week. This will slowly add moisture to the soil but avoid any shock or root rot.
To prevent underwatering from causing brown leaves on your Calathea in future, there are a few things you can do. Firstly, ensure that you adjust your watering schedule throughout the year as your Calathea will need more water during the warmer months, and can dry out more when you’re using the central heating for several hours each day. Using a moisture meter can help to figure out once the soil has dried out and your Calathea needs more water.
You might also choose to use a self-watering pot or self-watering globes which means you don’t even have to remember to water your Calathea on a regular basis as these will do all the work for you.
Brown Calathea leaf tips can indicate water sensitivity
Another cause of brown leaf tips is fluoride sensitivity. If you live in a hard water area, the chlorine and fluoride in the tap water can cause brown tips. This is because over time the chemicals will build up in the soil and prevent the roots from picking up the needed nutrients. There are a few ways to stop this from happening that don’t involve investing in a really expensive water purification system for your home.
Firstly, you can collect rainwater and water your plants with that as the levels of fluoride and other chemicals will be much lower than the treated water out of your tap. Secondly, you can leave a watering can full of water out for around 24 hours. Over that time a lot of the chemicals will evaporate from the water.
This isn’t an instant fix and there may be a few brown leaf tips that develop every now and again but it should stop the problem from developing rapidly.
Dry air can cause brown leaf tips on your Calathea
Low humidity levels can also cause brown Calathea leaves. This tends to start off as brown leaf tips, but can gradually take over more of the leaf if the problem persists. Calatheas like a little higher humidity than the average home so you need to take some steps to increase this. Here are our top tips:
Mist your Calathea’s leaves
Using a spray bottle, mist your plant a few times each week. Make sure to do it in the mid-morning though as you want to leave enough time for the water to evaporate before it gets dark as the cold air at night will cause damp leaves to rot.
Use a pebble tray
Fill up a tray of pebbles add water to about the halfway point. Place your plant on top and the water will evaporate around the plant slowly. You want to make sure the water level does not reach the pot as the roots will rot if they are sitting in a pool of water.
Wash down your Calathea
Wash down the leaves of your Calathea in the sink or shower. This is a great quick fix but it’s a fairly short-term solution so you’ll want to be doing other things too to prevent more brown leaves. Make sure to leave your plant in the shower for about half an hour after washing so the excess water can run off. Otherwise, this may waterlog the soil!
Invest in a humidifier
This is the best long term solution in terms of preventing any more brown leaves but it does need a little bit of upfront spending (although they are very affordable). They can keep quite a consistent level of humidity around your plants so you don’t need to remember to mist or change out the water in the pebble tray.
We recommend this humidifier from Amazon – our Calatheas love it!
If you aren’t sure of the humidity level in your home then it is a good idea to pick up a digital humidity monitor. They are very affordable little devices that will monitor the level in the room and help you to figure out if dry air is causing your Calathea (and other houseplants) to develop brown leaf tips. They are a must-have for every plant parent and have saved us from a lot of brown leaves in the past.
Brown leaves can also indicate temperature shock
Hotspots or cold drafts can also cause your Calathea to develop brown leaves. Hotspots can occur when your plant is too close to the window and is receiving a lot of direct light or if it is near a radiator or heating vent. It can be difficult to notice hotspots because the heat disperses around the room and it’ll feel like a normal temperature to you. Make sure you are ventilating the room well and avoid putting your Calathea within 1 metre of any radiators.
Cold drafts are also your Calathea’s worst enemy. A consistent stream of cold air coming in from outside through cracks in doors and windows can be quite harmful to your plant. This is especially dangerous during winter when temperatures can really drop. Make sure you draft proof any doors or windows that your houseplants are close to.
Like with humidity, it can be pretty difficult to figure out if the temperature is right for your Calathea. Whilst it may feel comfortable for you, there might be hidden little drafts or small hotspots forming in the room without you noticing. Use a digital thermometer to keep track of any fluctuations so you can be assured that your Calathea is in the right spot. Often, you can get one device that will measure both humidity and temperature and these are a real win for plant parents.
Causes of brown spots on a Calathea
If you have noticed that your Calathea has started to develop brown spots, but it’s not turning the entire leaf brown yet, then this is also definitely a sign of unhappiness.
Whilst some of the same factors can cause brown leaves as well as brown spots (such as water sensitivity, dry air and cold temperatures), there are some other factors to consider.
Brown spots can be caused by pests
These are a plant parents’ worst nightmare as they can very quickly start exhausting your plant and turning it brown. Pests such as spider mites will start to cause small brown spots across the leaves of your Calathea. Because spider mites love thin leaves, Calathea plants are the perfect spot for them to live.
The best way to identify Spider Mites as the culprits of your Calathea’s brown spots is by looking under the leaves for white webbing. Spider Mites are web spinners so there’s one telltale sign that they are present on your houseplant.
As soon as you’ve identified Spider Mites on your Calathea you should isolate it from any other plants nearby and you should check those over for any signs too. Pests can easily jump between leaves that are close.
There are a few ways to get rid of spider mites. Firstly, they hate high humidity so make sure to mist your plant frequently, wash it down in the shower and use a humidifier to get rid of them.
You also want to remove as many of the infected leaves as possible to curb the growth of the infestation.
You should also pick up an insecticidal spray and give your plant a spray down to kill any that are left on your Calathea.
Brown spots on a Calathea can also indicate sunburn
Whilst they need lots of light to thrive and photosynthesise, there is such thing as too much light. As Calathea plants have quite thin leaves, they can burn pretty easily when exposed to bright intense direct sunlight. This will show up as dry brown or yellow spots across the leaves of your Calathea.
The brown spots will also usually be on the side of the plant that is getting hit and dried out by the sunlight so that’s something to look out for when diagnosing the issue.
Although the brown spots are irreversible, preventing the problem from causing any more damage to your Calathea is pretty simple. All you need to do is find a new spot that suits your Calathea’s needs a little better. Find somewhere that doesn’t receive any direct light and move your Calathea there during summer. In winter, brown spots caused by sunburn are less of a concern as the sun is weaker and the days are shorter. This means you can get away with placing your Calathea a little closer to the window during the winter months.
You might also choose to pick up a light meter to monitor how much sunshine your Calathea is getting and figure out if you might want to move it to a slightly shadier location.
Should I cut the brown leaves off my Calathea?
Once your Calathea has developed brown leaves there is, unfortunately, no reversing this. The leaves will not return to their original colour or pattern. This might leave you wondering if you should leave the leaf on your plant or cut it off.
If it is just the leaf tips that have turned brown then we encourage you to keep those leaves untouched as this will not harm the plant. Although it might not look good aesthetically, we recommend keeping the leaf. Sometimes cutting off the leaf tip can look a little strange.
If the leaf has developed a few brown spots, then again we would recommend keeping the leaves on your Calathea as long as the majority of it is healthy.
However, if the whole leaf has turned brown then it is probably best to cut it off! You don’t want your Calathea to waste nutrients and energy trying to revive the dying or dead leaves. Instead, you want to encourage new healthy growth.
When removing the brown leaves on your Calathea, always cut them off with a sharp blade. Never rip the leaf off as this can damage the stem tissue of your plant.
To learn more about how to care for your Calathea plant, check out our Plant Index page which includes all the different Calathea varieties and their care guide. You’ll find detailed information about how to care for each one and prevent common issues from occurring again in future.
If you are struggling to keep your Calathea alive, and the issue keeps getting worse, then you might want to think about propagating your Calathea to save at least some of it.
Written by Joanna Turner