Architecturally stunning, with blooms that can even last for months and, let’s not forget, many healing and medical properties, it is no surprise that aloe is spreading from garden to garden all over the world, and with small varieties like Aloe dorotheae, Aloe ‘Guido’ and Aloe aristata, it has made the leap from sunny Mediterranean yards to indoor spaces as well.
It is an easy to grow succulent, with very few needs, however, sometimes, you will see that its leaves turn brown? Why Is your Aloe Vera plant turning brown?
Aloe plants turn brown due to overwatering, causing root rot, or insufficient water leading to dry leaves. Fungal infections can also result in brown spots. If your aloe vera plants are suffering from a case of root rot, repotting into fresh new potting media should resolve this issue and set it on the path toward recovery!
If you have or plan to have an aloe, and if its leaves are turning brown (or you are scared they will), then look no further, because, whichever the cause, you will find the solution in the article you are going to read.
7 Reasons Why Aloe Plants Turn Brown
When your aloe plant starts turning yellow, you may be wondering what’s going on.
A few things can cause your Aloe plant to turn brown including: not enough sunlight, overwatering, or the soil being too dry. Let’s take a look at each of these problems so we can figure out what might be causing this issue with your Aloe plant.
1. Aloe Plant Turning Brown Because Of Overwatering
Overwatering is one of the primary causes of yellow leaves on aloe plants.
Aloe plants have few stomata; this means that they cannot perspire water as effectively as other plants. Excessive water accumulates within the meristem (the “pulp” inside the leaves, which, if we want to define it properly, is a tissue of non specialized cells).
When too much water is compressed within it, the pressure it causes can literally break the structure of the tissue. This will cause not only a change in the texture of the tissue, but also of the color, which will start with yellowing then turn brown in advanced phases.
With all succulents, overwatering is arguably the most common cause of bad health and, in some cases, even death.
It is far too easy to feel “generous” with these plants and give that extra watering “because it’s hot”, but while we think we are helping our plant, in reality we are inflicting damage, and, far too often, even lethal problems.
If your aloe is brown because of overwatering, the chances are that it may already be too late to save the whole plant. Browning is a late symptom of overwatering, so, look out for earlier symptoms including:
Is your aloe turning brown because of overwatering? Two different cases
When the plant turns brown because of overwatering, you may have two cases:
Curing Aloe Plants With Localized Browning
If the yellowing problem is localized on the leaves, you can take some simple and fairly limited stamps to solve it:
This, in case the problem is limited to a few leaves, should normally do the trick
Curing Aloe Plants With Browning At The Base Of The Stem (Root Rot)
However, if the browsing (or yellowing) is at the base of the stem, the risk is that you may lose your plant. Your action, therefore, will have to be much more drastic.
In case you have only saved some leaves, you can try propagating your plants with leaf cuttings following exactly the same steps above.
However, you are less likely to succeed than if you have saved part of the stem.
2: Aloe Plant Turning Brown Because Of Underwatering Or Excessive Sunlight
When leaves dry up, the chloroplasts start losing chlorophyll, which as you know, is green; this of course, causes a change in the coloring of the leaves of your aloe plant which will, in their last stage, turn brown.
Your aloe may turn brown also if it becomes dry; this is most likely due to excessive sunlight, heat or underwatering. Yes! Aloes like very warm places, but they prefer temperatures between 55 and 80oF (13 to 27oC); when the temperature goes above that range, their leaves can start getting spots of brown color on them and even whole dried-out leaves will be present on your plant.
However, the browning will be different from that due to overwatering.
If this is the case with your plant, check the soil. If it is dry, then you will be sure about the cause of the browning.
The dry leaves will not be a health hazard for your plant. Aesthetically, though, they may not look great. If you wish, you can cut them with a sharp and sterile blade.
Now, however, there is another thing you should do if you can:
3: Sudden Changes In Temperature And Climate
Even a sudden change in temperature can cause a browning leaves on a aloe plant. The plant’s cells may not withstand the sudden shift and die, in doing this, they will change color.
Many of us like to keep houseplants indoors in winter and then take them out during the summer months, especially with succulents like aloe plants.
In fact, plants do like a bit of fresh air, and they welcome those days in the open air.
However, every place has its own characteristics, both indoor and in the open air.
If the conditions indoor are very different from those outdoor, you may cause stress to your aloe when moving it from your sitting room to your terrace.
For example, the light in its indoor place may be fairly dim or diffuse, it may be sheltered from winds and maybe the humidity is fairly high, while your terrace is south facing, and in a windy spot.
When the move happens, plants that find the difference a bit stark may respond with:
What can you do about it? If it has already happened:
Nevertheless, the best solution is prevention. Plan your plant’s “change of home” and allow it to acclimatize to the new place:
4: Aloe Turning Brown Because Of Wind And Draughts
Wind has a drying effect; when tissue dries up, it turns brown. And this also happens with aloe pants. Aloe is better sheltered from wind, especially strong wind.
In fact, sometimes, plants can suffer from wind scorch, which is when the leaves dry up and, in fact, go brown, because of draughts and wind. To avoid this:
5: Aloe Turning Brown Because Of Excessive Cold
Brown in aloe plants that have suffered excessive cold is a bad sign indeed; it is a result of tissue decay and death and, in some cases (when accompanied by softening and jellification of the tissue) it shows that the tissue of your plant has started rotting.
Aloe is a plant that loves warm weather; in fact, this succulent hails from Africa, the Arabian Peninsula and some islands in the Indian Ocean, though it has become naturalized around the Mediterranean Basin.
Still, you don’t associate its tongued leaves with Greenland, do you?
While some specimens (adult and healthy) and species may withstand temperatures as low as 32oF (around 0oC), when the temperature drops under 40oF (about 5oC), these plants will suffer and won’t do well at all.
In fact, you should always try to keep it above 55oF (or 13oC).
Still, the odd cold day happens, and, in these cases, you may notice a change in the coloring of your plant’s leaves:
Depending on the severity of the problem, you may or may not be able to save your plant.
6: You’re Feeding Your Aloe Plant Wrong
If your aloe receives excessive nutrients, some of its tissue may die. This, of course, will result in a change in the color of the tissue that, when dead, turns brown.
Don’t confuse love with abundance when it comes to feeding your aloe plant; in fact, you should only feed it very sparingly, never more than once a month, and only from spring to summer. Then, suspend feeding altogether.
Like most succulents, aloe does not like soil that is too rich in nutrients, and over feeding may be a problem. If you use a general fertilizer, make sure you only give it half dose.
Of course, organic fertilizers are better because they do not pollute, do not impoverish the soil in the long run and they release nutrients slowly.
If you give your aloe too much fertilizer, the salts accumulate in the soil and you can witness what gardeners call fertilizer burn, or tip burn, as it manifests itself as a browning of the tips of the leaves.
You may have seen this fairly often… Healthy looking plants with tips that appear to be dry, brown and burnt…
If you only see one or a row tips, then the solution is simple:
Suspend fertilizing immediately, even for a full season, and start again the following spring.
If, however, the problem is widespread, you may wish to change the soil, so:
Repot your aloe in new, light and well drained potting soil. This, of course, on top of suspending feeding.
7: Aloe Turning Brown… Is It A Fungus?
But maybe the browning can be due to fungi; in this case, the change of coloring may be due to either the color of the fungus (or its spores), or lacerations caused by it in the tissue of the plant.
Aloe is a very strong and usually disease free plant. However, even they can get fungal infections every now and then.
This does not usually happen when in the wild or places with dry winters, but indoor spaces are not always ideal for them to spend their winters. This is usually due to:
There are three main fungi that can find your aloe a good place to live, and they do not respond equally to treatment:
Gray Mold (Botrytis Cinerea)
It is called gray but it appears gray brownish, and what you see is actually clusters of spores. These will appear as a thin layer on top of the leaves and stem, forming like a veneer or patina.
This is quite an insistent fungus; if you take it soon, you can try to stop it with organic fungicides like copper soap, but that won’t be enough.
You could try using neem oil at a very early stage, but it is fairly weak with gray mold and you will in any case need to repeat the treatment (and still burn the leaves).
Keep an eye out for gray mold especially in spring and in early summer, when it is more likely to occur.
This is a particular fungal infection caused by a genus of fungi called Colletotrichum. It looks a bit like rust, which is brown at fist sight but close by it is more of a red-orange shade, along the lines of of cherry wood.
These start as small spots but they multiply and grow fairly fast. In this case, you should:
Root And Crown Rots (Phytophthora)
This fungus is bad news. There are no actual treatments that work well with this mold, and your best chance is to prevent it.
It starts from the roots, which will lose feeder roots (those tiny little “hairs” that grow alongside main roots).
Then, it will move up, and maybe only then you will start to notice it as a series of brown lesions.
With many plants, it then affects the leaves, making them turn first yellow, then wilt and then, usually, they remain brown and dry attached to the stem.
To avoid it:
If you your plant catches the fungus, this is what you can do:
Now, we did say that this fungus does not respond well to treatment, however, recent studies show that three species can be controlled by using some simple mixes.
For Phytophthora nicotians, using a mix of clove oil, neem oil and pepper extract on roots, stem, leaves and (in case you can’t uproot it) even the soil can reduce the fungus significantly.
With Phytophthora capsici, spraying water with drops of red thyme, oregano and palmarosa essential oils can have good results.
With Phytophthora nicotianae, extracts of clove and cassia sprayed onto the plant can reduce it very significantly, by 99.6 and 99.2% respectively.
Fortunately, Phytophthora is not a common problem with aloe plants, it tends to attack other plants, especially some like raspberries etc. that we tend to grow outdoors as crops instead.
Brown aloe problems and their solutions
As you can see, there are many reasons why an aloe may turn brown, some are fairly common (overwatering, heat, over-feeding, even underwatering…) and some are less common (some fungi, for example).
Most have fairly simple and straightforward solutions, and nothing that requires a degree in botany or extremely laborious processes.
Still, your best chance is to avoid these problems so… Find it a good, dry and ventilated place, give it a light and very well drained soil, do not overwater at any stage nor underwater for long and be stingy with feeding.
If you do these things consistently, and you keep an eye out for many signs of bad health in your plant, you are very likely to have a very happy, very healthy and very green aloe indeed!
Or red… silver… dotted… even pink, depending on the variety of course, but not brown!
Amber Noyes was born and raised in a suburban California town, San Mateo. She holds a master’s degree in horticulture from the University of California as well as a BS in Biology from the University of San Francisco. With experience working on an organic farm, water conservation research, farmers’ markets, and plant nursery, she understands what makes plants thrive and how we can better understand the connection between microclimate and plant health. When she’s not on the land, Amber loves informing people of new ideas/things related to gardening, especially organic gardening, houseplants, and growing plants in a small space.