Aloes are some of the most popular and low-maintenance succulents around. Their hardy nature and need for minimal care and attention, coupled with their beautiful shape and many medicinal benefits, is why they are widespread and included in most succulent collectors’ gardens.
One of the most common problems experienced by aloe owners is the plant turning red.
The most common causes of an aloe turning red are too much water, too much sunlight, temperature changes, too much fertilizer, lack of nutrients, incorrect potting mix, pests and disease.
In this article, we will discuss each of these causes and how to remedy each one. So, if you have an aloe that has suddenly turned red, keep reading to learn how to fix it.
Why is my aloe turning red?
1. Too much water
Too much water or overwatering is one of the most probable reasons your aloe is turning red. This may be due to you giving the plant too much water every time you water it, or watering it more frequently than you should. Another factor that could lead to overwatering is poor drainage due to the incorrect potting mix or a lack of drainage holes at the bottom of the pot.
Succulents, in general, do not need to be watered much because they can store plenty of water in their leaves to act as reserves in the event of a drought. They need proper soil drainage because their roots are sensitive to damage from standing in waterlogged soil.
Overwatering can be quite tricky to spot in its early stages because the signs of an overwatered aloe typically appear only when the plant has been overwatered for some time.
Signs that you have an overwatered aloe include colored spots that can appear red or brown on the plant’s leaves, and if the leaves feel soft and mushy to the touch.
The worst-case scenario for an overwatered aloe is root rot.
Root rot is a condition that can develop when the aloe has been overwatered for some time and its roots are constantly standing in soggy soil. The roots will drown because they are unable to get access to oxygen, which they need to survive. The dead roots will become susceptible to opportunistic pathogens, which will help spread the rot to the rest of the plant until the entire plant is compromised and could even die.
Remedy
If you suspect that overwatering may be the reason your aloe is turning red, stop watering it immediately.
You will need to get as much water and moisture out of the soil as you can, so that it can dry out completely.
If you think that the plant may have root rot, remove it from the pot and wash the soil from the roots. Do this gently, because the roots will be fragile in this condition.
Inspect all of the roots closely and check for any sections that have turned brown or black. These roots are rotten and will need to be removed. Use a sterile pair of scissors to cut the rotten roots away until only white, healthy roots remain.
Lay the plant on a dry paper towel and allow it to air dry for a couple of hours. When the roots are dry, you can plant the aloe in a pot that has drainage holes, using a new potting mix that is well-draining and airy.
You can even create your own drainage holes at the bottom of the pot with a drill. These holes, along with the well-draining soil, will let any excess water flow though so that it does not stagnate around the plant’s roots.
There are plenty of commercially-available succulent soil mixes in your local store. These contain substances such as perlite, pumice or coarse sand, that make the soil more porous.
Lastly, you will need to adjust your watering techniques to avoid further overwatering. The best way to determine whether your aloe needs to be watered is by touching the top two inches of soil with your fingers. If the soil is dry to the touch, water the plant, but if it is still damp, wait one or two days before checking it again.
On average, an aloe typically needs to be watered every 10 days.
2. Too much sunlight
Your aloe could also be turning red because it is getting too much sunlight. The redness on the leaves may be sunburn.
If you live in a place with a very hot climate where your aloe is getting direct sunlight for most of the day, this puts your plant at a higher risk of getting sun damage.
There are some aloes that prefer indirect light and it may be best to keep them indoors near a window or on a patio or porch where they can get some shade for a few hours a day.
Your plant can also be sensitive to sunburn if you have recently moved it from a cold climate to a hotter climate. Remember that plants also need time to adjust to new surroundings, so make sure that you help it transition properly.
Remedy
Fortunately, fixing redness on a sunburnt aloe is as simple as limiting its exposure to the sun.
The moment you see the aloe turning red, move it immediately to a shadier area, such as under a large tree or on your patio. The plant still needs light to survive, so if you take it indoors, placing it near a window should be good enough while it recovers.
As we mentioned above, if you move the plant from a place with not much sunlight to a place with lots of sunlight, move it gradually by slowly increasing the number of minutes it spends under the sun every day, until it has acclimatized properly to its new surroundings.
3. Temperature changes
A change in the temperature around it can also cause aloe’s leaves to turn yellow or red.
If you leave the plant outdoors during the summer and fail to take it indoors as winter is starting, this can lead to leaf damage from stress due to environmental changes.
Remedy
If you live in a region where there is a big change in temperature between winter and summer, you need to be more vigilant about when you bring your plant indoors so as not to expose it to temperature extremes.
Remember that, whether you are bringing it in from the outdoors or taking it outdoors after keeping it indoors, it should be a slow transition.
If your aloe is an indoor plant, move it away from windows that let in too much light during hot summers. Choose a west-facing window and place the plant about a foot away so that it gets some shade.
4. Too much fertilizer
Another reason your aloe is turning red could be that you have given it too much fertilizer and salts may have built upon the top layer of the soil.
Minerals that are present in the soil are converted to chemical salts. These minerals include potassium, phosphorus, and nitrogen that the plant needs to survive.
If you give the plant mineral-heavy fertilizer, or if you fertilize it when it is not actively growing, you can cause a salt build-up in the soil which can cause root damage.
Remedy
If you see a build-up of salts on the soil, you need to scrape it off as soon as possible. You will then need to flush out as much of the excess nutrients and minerals from the soil as you can.
Water the soil in the pot with a volume of water equivalent to five times the volume of the pot in order to flush out the excess fertilizer in the soil.
The amount of light your plant gets should also factor into how often you fertilize your plant.
The more light a plant gets, the more it needs to be fertilized if you want it to thrive. This means that a plant that likes low light should only need to be fertilized once a year. Aloes will typically need fertilizing one to two times a year.
Tap water can also be a source of unwanted minerals for the plant. Try using rainwater or distilled water on your plant instead. If you do not have access to distilled water or rainwater, use an external water filter to remove the minerals in your tap water before you water your plant.
5. Lack of nutrients
As much as an excess of nutrients and minerals is detrimental to your aloe, so is a lack thereof.
Your aloe can also have red foliage if it does not have enough of the nutrients that it needs.
Yes, succulents are much less affected by this than other plants, but that does not mean they do not need the nutrients.
A lack of essential nutrients and minerals such as magnesium and nitrogen can lead to a lack of chlorophyll, and without chlorophyll, the aloe cannot create its own food to survive.
Remedy
Using the right kind of potting mix is usually enough to provide your aloe with what it needs. Potting mix that is specifically designed for succulents contains slow-release nutrients, which is ideal for your aloe.
6. Incorrect potting mix
We have already mentioned that it is very important to use the correct potting mix for your aloe. If you are using regular potting soil, this can negatively affect the plant and its leaves may turn red.
Remedy
The only way to fix this problem is to repot the plant as soon as you can.
You will need to ensure the plant is as happy as possible before you do something as stressful as repotting, so water it two days before you plan to repot it. This will also help soften the soil before you remove it from the pot.
Choose a potting mix specially designed for succulents or cacti. You can also make your own potting mix by combining three parts regular potting soil, one part perlite, and one part coarse sand. This mix will allow excess water to pass through easily and will make the soil airy and porous so that the roots can get the oxygen they need to survive.
7. Pests
Most succulents are unaffected by pests and are even often considered to be pest-resistant, but they still attract certain pests for which they provide water and shelter due to their rigid foliage.
The presence of these pests may also be the cause of the redness on your aloe’s leaves.
One of the most commonly observed insects on aloes is the mealybug. This bug uses its mouth to pierce through the plant’s tissue and feed on the sap. One or two of these insects may not cause noticeable damage, but the longer they are allowed to live on the plant, steadily increasing their population, the more obvious their damage will be.
Colonies of mealybugs look like red splotches at the base of the aloe.
Remedy
Remove the mealybugs by dislodging them with a steady stream of water or by spraying them with a solution of dish soap and water. Rubbing alcohol is also effective as a spray to eradicate mealybugs. Repeat the process once a week until there are no more bugs to be found.
Another insect that feeds on aloes is the scale insect, which also pierces the plant tissue to feed on the sap. You use the same methods described above to get rid of scale insects. Make sure to keep the infested plant in a different area away from your other plants so that the insects do not spread.
8. Disease
Mold and fungi can grow on your aloe and can also cause it to turn red or brown. The growth of these pathogens is due to the soil in the pot being unable to dry out completely between waterings.
Remedy
If you see white mold or fungi growing on the top layer of the soil, use an old spoon to scrape them off. This is the first step in removing them from the soil.
In order to keep mold or fungi from growing on the soil and possibly damaging the roots and foliage of your plant, allow the soil in the pot to dry out between waterings.
Remember that aloes are succulents that come from some of the driest and most arid places on earth, so they are more than adept at surviving drought. It is far better to err on the side of underwatering than overwatering these plants.
You can also let the plant get more light so that the soil dries out faster, and place it where there is good air circulation which will also help dry the soil out between waterings.
Before watering your plant, check that the top two inches of soil are dry.
Conclusion
Aloes are some of the most resilient and low-maintenance plants, so it takes a lot for them to become stressed and for this stress to manifest as red foliage.
The most common causes of an aloe turning red are too much water, too much sunlight, temperature changes, too much fertilizer, lack of nutrients, incorrect potting mix, pests and disease.
Figure out what exactly is causing your aloe to turn red and remedy it accordingly to get the plant back to normal and growing properly as soon as possible.
Image: istockphoto.com / Alberto Masnovo