Aloe Leaves Turning Black (7 Causes And How To Fix It)


Indoor aloe leaves turning black gradually.

Indoor gardeners grow aloe vera for the aesthetic appeal and medicinal properties. Aloe turning black is a problem that you may face if you have any. 

Luckily you are at the right place to find the solutions. I work with numerous gardeners and farmers to solve their problems as a part of my job.

So, I am going to share my real-life experience solving aloe turning black problems.

Aloe vera turning black is a signal of serious care mistake and the plant is under stress. There are other factors like improper watering, dry air, fungal infection, contaminated soil, frostbite, thrips infestation can cause aloe to turn black. 

In order to find out how to fix your aloe and how you can prevent it from happening, keep reading. 

7 Common Causes For Aloe Turning Black And How To Fix them

I am sure you already get that, aloe turning black can not occur because of one single reason. So, you have to identify the reason first before you can take action to fix the problem. 

Here are the potential reasons and how you can fix them. Let’s get started.

Over-watering

It may sound strange that one of the common causes of aloe blackening is overwatering. Overwatering makes the soil remain abnormally dump and the roots begin to rot.

Now, if the roots are rotten, the plant can no longer absorb nutrients and water from the soil.  So, nutrients and water will not circulate throughout the whole plant. Consequently, the leaves tend to turn black or yellow.

Overwatering, therefore, has the same consequence as a lack of water. The only difference is the root can not uptake water although it is available. 

How to fix

Aloe is a plant from the desert, so it can survive a lack of water for a long time.  If you find that the soil is far too wet or even soggy, place your plant in a warmer place to help the water evaporate faster. 

When the condition is really critical, you may have to trim the bottom where it is black, to normal living tissue.  Cut off the affected root part completely. 

Carefully inspect the root, it should be clean, without dark spots. Sprinkle the wound with charcoal and dry a little.  Then plant your aloe in a new pot with well drainage capacity soil mix. 

Make sure your pot has water drainage holes at the bottom. This is very important to prevent the root rot of aloe vera.  Water your aloe from the below when the soil is completely dry. 

I have written a detailed article on: How to Save Overwatered Aloe Plant

Lack of water

It is obvious that the drying and blackening of the leaves are symptoms of a lack of water. This problem is less common for outdoor aloe that benefits from rainwater. 

In summer your aloe vera needs more water because in this period aloe increases the physiological activities and growth. Also, water evaporates quickly due to the high temperature. 

So, if you do not water frequently in this season your aloe will show symptoms of lack of water. 

Beware of seasons like spring and autumn, which are already wetter periods and during which we tend to neglect water, thinking that nature has drunk enough. But it’s not always the case. 

If the plant turns black, it means that the plant sap with nutrients did not make it to the ends. This is why you should pay special attention to watering. 

How To Fix

I hope you have realized the importance of hydrating the plant well, the water present in the substrate is an essential component for the production of sap. 

To fix this problem try to stay consistent in your watering. If the water dries quickly due to direct sunlight then it may be necessary to reconsider the place where you placed your plant. 

Do not let your plant remain thirsty for a long period of time during summer. Check the soil regularly to determine if your aloe vera needs to drink water. 

Dry Air

Dry air is the second most common cause of aloe tip and edge blackening. If your aloe pot is placed high up, they are more often confronted with dry air. 

This problem often occurs in winter, as you heat your home and the plant makes up for it by transpiring more. So, low humidity for a long time will cause serious damage to you aloe vera. 

How to Fix

You need to water your houseplants more frequently or find a way to humidify the air in your house or apartment.

You can spray the aloe vera to keep it cool. This helps to a great extent but you have to do it frequently.

Another easy and smart solution is using a humidity tray. If you use this tray you do not have to spray your aloe frequently. This humidity tray will automatically control the humidity around the plant.

A very simple evaporation mechanism works here. Water evaporates from the tray and keeps the plant protected from excessively dry air.  Any flat container can work as a humidity tray. 

Here is a helpful video on how you can make and use a humidity tray.

Aloe Vera Leaf Spot Disease

This is something that you do not want to deal with. I was researching on the internet about black spots on aloe leaves but there was no legit information. 

Someone says this occurs because of care mistakes, some say this bacterial or fungal disease. Finally, I found a research paper on the leaf spot of aloe vera. This scientific paper confirms this as a fungal (Nigrospora oryzae) disease. 

How To Fix

So, if you notice a black spot on any leaf, you need to take drastic action. Because these spots are going to spread all over the plant. 

You can try applying any kind of fungicide available in the market. But I suggest you should cut off the infected leaf at the beginning before it spreads throughout the plant. 

If more than one leaf shows the same symptom then cut off all the leaves with symptoms of black spot. Do not worry, new leaves will come out soon and your aloe will be alright. 

Fertilizer Burn

Overfeeding is not good for plants also. It can happen that you have overfertilized your aloe vera without even realizing it. 

And suddenly you find that your aloe vera plant showing symptoms like blackening of stems staring from the root zone. When excessive nutrients are carried to the leaves, it becomes dark and eventually black. 

How to fix

If you find out at an early stage you can fix the problem and solve your aloe vera from further damage. At first, prune the affected parts of the plant.

Fertilizer washes away with the water. So wash the over-fertilized soil with a lot of water. Do not let the water stand in the pot. 

So, before fertilizer application make sure you read the instructions on the package. Make sure you apply the right quantity depending on your pot and plant size. 

Organic fertilizer can be a great solution for this. Because an overdose of organic fertilizer will not damage your aloe. It is slow releasing and aloe vera loves them.

Frostbite

Frostbite can be fatal for your aloe vera. If you are from an extremely cold area where the temperature drops drastically in winter then you need to be careful about your aloe vera.

When the temperature drops to freezing point the plant sap also freezes, it can not continue carrying water or nutrients.

So it gets dehydrated and cells die from the cold bite. And you will seed that your aloe vera has turned black.

How to fix

The bad news is you can not revive the damaged part of your aloe from frostbite. So it is important that you take care of your plant before it gets hit by frostbite.

When the temperature starts to drop, bring you aloe vera inside the room and keep it warm. It will need a minimum of water during winter because this is the rest period for plants. 

Thrips Infestation

These are very tiny insects of 1-2m,m in size.  They reproduce very quickly in high humidity and temperature.

If you see small black dots on your aloe vera leaves, then inspect your plant carefully for thrips. Because these tiny insects suck on the juices of your aloe vera and leave black dot traces of their presence. 

How to fix

Thrips and soft-skinned insects. You can control this insect with insecticidal soap water. If the infestation is intense you may consider applying neem oil.

It is better to prune the infected plant parts. Also, natural beneficial insect-like pirate bugs work great against thrips. You will find beneficial insects in gardening stores.

Conclusion

Now you have the knowledge of how you can fix if your aloe is turning black. So, let me know,  have you found the solution here?

If yes then which solution are you going to apply? Let me know if you have any suggestions or any other solution other than these. 

Arifur Rahman

I'm the owner of gardenforindoor.com. After completing my bachelor of science in agriculture, I'm serving as a civil service officer at the Department of Agricultural Extension, Bangladesh. I started Garden For Indoor to make your indoor gardening journey easy and enjoyable.

Recent Content