Aloe vera is a perennial succulent native to Africa’s hot, dry, warm regions. Its beautiful leaves, drought resilience, and soothing gel have earned it a place in windowsills and gardens worldwide.
Although these plants are widely adaptable and easy to care for, they are not immune to problems. Blackening foliage and dying leaves are clear signs that a plant is unhappy. Let’s dig into six potential causes for a black, dying aloe plant and how to fix them.
Why is My Aloe Turning Black and Dying?
Remove your dying plant from its pot to examine the roots, removing any unhealthy root tissue before repotting.
The quickest way to help a dying aloe plant is to remove it gently from its pot and examine the roots. Use sanitized pruners to remove rotten, mushy, or fungal-infected portions. You can also remove dead or blackened leaves. Rinse the roots, then refill the container with an extra well-drained soil blend of vermiculite, pea gravel, and perlite.
Alternatively, purchase a cactus or succulent potting mix. Replant the aloe and place it in an area with bright, indirect sunlight. Wait a few weeks for the leaves to regenerate. Do not water until the soil has thoroughly dried out.
6 Reasons for a Sad Aloe Vera Plant
Even the most robust aloe vera plants can face issues when their care or environment changes. Blackened leaves or dying foliage are clear symptoms of distress. Always pay attention to what your plant is showing you because the visual appearance provides clues to the root cause of the issue.
When diagnosing these symptoms, fix one thing at a time and remember that more than one problem can be at play. Your plant may take several months or even a whole season to recover, but most aloe vera plants can be revitalized with proper care.
Overwatering
Overwatering aloe plants, especially in pots with poor drainage and humid climates, causes root rot.
Excessive watering is usually people’s most common mistake with aloe plants and succulents. Overwatering your aloe leads to suffocated roots that eventually rot. This problem is compounded when aloe grows in a pot with poorly drained soil and a humid climate.
While water is essential for plant survival, these species have adapted to long periods of desert drought. Aloe vera still enjoys water every couple of weeks to months, depending on conditions, but houseplant lovers sometimes go overboard.
Aloes are naturally arid, drought-resilient plants that store moisture in their leaves as a gel. Excessive moisture in the soil invites fungi to colonize roots, turning them mushy and black. When root hairs and tissues begin rotting, the plant ironically can no longer uptake water. Above ground, the leaves begin to yellow and turn brown or black. They are cut off from nutrients and water, making it impossible for the leaves to photosynthesize and retain their healthy green color.
How to Fix It
Aloe vera does best when you adjust your watering schedule to let the soil thoroughly dry out in between waterings. Avoid watering any time the soil feels wet. If you stick your finger in the soil and your skin comes out dirty or moist, don’t water. Once you’ve identified that the soil is too moist, you can either let it dry out for several days to a week or investigate further. The issue of overwatering is very closely correlated with root rot and poor soil drainage.
When the soil is dry several inches down, and the leaves appear turgid and upright, you can water again. Any time you water aloe, only pour the watering can until moisture comes out of the bottom drainage hole, then stop.
If growing in a container without a drainage hole and catchment tray, transplant the aloe immediately and check that the roots haven’t rotted. If growing in the ground, you’ll likely need to uproot the plant, amend the soil to improve drainage, reduce watering, and replant. In extra-rainy climates, it’s often best to move aloes into pots in an area protected from rainfall.
Once the soil dries out, monitor to see if your plant perks back up. If it doesn’t, move on to examine the symptoms below. You can remove blackened or brown leaves to encourage new growth, but avoid defoliating the plant because it will still need healthy leaves to regenerate.
Root Rot
Overwatering and poor drainage can cause root rot, common in succulents and cacti.
Root rot almost always occurs in conjunction with overwatering and poorly drained soil. It is particularly common in succulents and cacti. Root rot is caused by pathogenic fungi that colonize the aloe’s roots and suffocate them. The roots become soggy, mushy, and black, eventually dying off. The rotten roots cannot uptake minerals or water.
Sometimes, you can smell a foul odor from the soil surface when the roots are rotting. Other times, you’ll only see the above-ground symptoms of yellow, brown, or blackened leaves that wilt and die no matter how much water is present. The only way to know that the roots are rotten is to dig up the plant and examine the root system.
How to Fix It
Most plants can be saved from root rot if some healthy root tissue remains. First, carefully remove the aloe from its container or dig it up from the ground. Turn the plant on its side, taking care not to break off any leaves. Brush away any soil and closely inspect the roots.
Healthy aloe roots appear thick, intertwining, and whitish-yellow or orangish-brown. The texture is firm yet pliable. Rotten roots look dark brown or black and slimy or mushy. Typically, the rotten areas will easily fall off when handled.
Use sterilized pruners or shears to cut away the rotten areas. Leave the plant out overnight on a towel in a dark, dry area so the cut portions of the roots can form callouses. This will help prevent re-infection. Dispose of all infected plant parts and dispose of the previous soil as well. Wash out the container, let it dry, then refill it with a fresh, well-drained succulent soil blend. Make a hole in the middle of the soil and place the plant back inside, then backfill. Avoid watering for a week or so until the roots can toughen back up and start regrowing.
If remediating an aloe vera plant growing in the ground, thoroughly amend the soil with the guidelines below regarding soil drainage. Once the rotten root parts are removed and the soil drainage is improved, you can plant it back in the same location and patiently wait for it to recover.
You will know aloe has recovered from root rot when young new leaves emerge and existing leaves perk back up or turn green. However, if any leaves are completely blackened or dead, they will not regenerate and should be removed.
Poor Soil Drainage
For healthy aloes, avoid overwatering and use well-drained soil with perlite.
Overwatering, root rot, and poor soil drainage can be a disastrous triple whammy for aloe plants. Often, when one of these issues causes symptoms, all three of the problems are at play. Any time you notice blackened, dying leaves, it’s recommended to repot or transplant them into better-drained soil.
Aloe plants need very porous, fast-draining soil that moves water through very quickly. They struggle in heavy clay soils and don’t prefer rich compost that holds onto moisture. The best soil for aloe vera is well-drained, sandy, or gravelly in texture. Succulent or cacti potting blends with perlite and vermiculite help enhance drainage.
How to Fix It
Use your hands or a shovel to gently uproot the aloe by digging around the plant’s perimeter and lifting it out of the container or garden bed. Prepare the new soil after examining the roots and checking for root rot.
The easiest way to ensure proper drainage is to purchase a pre-blended cactus or succulent blend. If you want to make your own or amend native soil, incorporate lots of sand, fine gravel, crushed rock, and perlite or vermiculite.
Before replanting the aloe, you can test the soil for drainage by placing a handful in a container and pouring water over it. If the water pools up on the surface and takes a while to drain, this is a major sign that it needs more aeration. Heavy concentrations of clay can impede water flow and make it accumulate on the surface. If the water rushes through the soil quickly, it is good to go! Replace your aloe and be sure it is planted at the same level as it was before.
Cold Exposure
Aloe plants may suffer in cold temperatures, especially young or damaged plants.
Aloe plants thrive in temperatures above 60°F. These warm climate plants may turn yellow or brown when exposed to cold temperatures below 40-55°F. Some mature, healthy plants in warm microclimate rock gardens can withstand the colder range of the spectrum, but young or damaged plants are the most vulnerable to the cold.
Cold exposure often occurs when houseplants are left outside or subtropical areas receive unexpected cold fronts. This temperature sensitivity is the primary reason why outdoor aloe vera is only recommended in zones 10-13. To grow aloe outdoors in northern climates, search for species like spiral aloe (Aloe polyphylla) or coral aloe (Aloe striata) that are cold hardy.
How to Fix It
After cold exposure, immediately move the plant to a warmer location. Depending on how harsh the cold was, some leaves may turn light, translucent, or soft. In this case, they need to be removed. But if they only appear yellow or brown, they may be able to recuperate once in a warmer space. Keep your aloe indoors in an area with bright, indirect sunlight.
Sun Scald
Avoid sunscald by gradually acclimating aloe plants to intense light conditions.
Aloe vera is a desert plant accustomed to bright, harsh sunlight. However, houseplants are often accustomed to less intense lighting conditions. The leaves can become scorched if aloe is suddenly moved from a windowsill outside onto a south-facing patio in the summer.
Moving from an area with partial shade or indirect light to a space with intense direct sun shocks the plant. Without sufficient time to acclimate, the leaves may quickly turn yellow, orange, brown, or black and begin to wilt. Sometimes, they take on a reddish hue after being burnt. While plants can recover, it takes a lot of time and patience for them to regrow.
How to Fix It
First, move your aloe to a shadier spot as soon as possible. Leave the sun burnt leaves in place to see if they revitalize. Provide a little extra water and wait several weeks for it to regrow. It may need more water than usual, but it’s important not to overwater. Protect the leaves from direct sunlight while they recover, but ensure they still get indirect dappled light through a window or a partially shaded garden area.
Never move an aloe plant into drastically different lighting conditions without acclimating it. If you want to move a houseplant outdoors for the summer, gradually introduce it to more light over several weeks.
For example, you might first move it from the middle of the room to a few feet from a south-facing window. Wait a few days, and then move it closer to the window. Once the leaves have adjusted and developed their natural sun protection, move the plant to the patio, where it is partially shielded from the afternoon sun.
Remember, plants don’t have legs, and they do not move in nature. If you are transplanting outdoors or moving aloe from one place to another, always do so gently and gradually.
Underwatering
Prevent blackening by checking aloe soil moisture and watering deeply but infrequently.
While uncommon, aloe plants can sometimes turn black or brown due to underwatering. This likely only happens in container plants left for several months without any care. Underwatered plants appear dry, shriveled, and brittle. The soil will be dusty and chalky, with no moisture at all.
How to Fix It
Check the soil moisture near your aloe vera every 1-2 weeks. Smaller pots need water more frequently than large containers or in-ground plants. Stick your finger in the soil to check the moisture level several inches down. When the soil thoroughly dries, it’s time to water again.
Water aloe plants deeply but infrequently. A large flush of water mimics the flash flooding and monsoons of the desert. Pour water until it flows freely out of the bottom drainage hole of a container, then stop. Check the plant in a few days to see if it has perked back up. Avoid bombarding it with moisture until you know it has absorbed the added water.
Final Thoughts
The most common reason for a black or dying aloe plant is root rot due to overwatering and poorly draining soil. These arid-climate plants must only be watered when the soil dries out. The water should drain through the soil profile rapidly. Plants may also display similar symptoms if exposed to excessive cold or a harsh change in sunlight exposure.
Uproot the plant, examine the roots, transplant to better-drained soil, and move to protected warm conditions while you patiently wait for the leaves to regenerate.
