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It can actually be very satisfying to take care of a cactus plant. Not only are these plants fun to look at, but they’re also not all that difficult to care for in most instances.
The fact that cacti enjoy dry environments and don’t need an abundance of water is well known. However, this doesn’t mean that problems can’t pop up when you’re taking care of a cactus.
You might have noticed that your cactus is turning yellow or brown recently. This is definitely not normal, and you’re going to want to determine what is going on so that you can correct any mistakes that are being made.
Read on to learn what to do about a cactus turning yellow or brown. This should allow you to make good decisions that will help you to save the cactus.
Sunburn Is a Possibility
You know that cacti are very hardy, but this doesn’t mean that they’re invincible. Your cactus plant likely enjoys hot and dry weather, but this doesn’t mean that it’s going to do well with especially harsh sunlight all the time.
It’s possible that your cactus could start to turn yellow from the top if it has been burned by the sun. Many people don’t think that this is a possibility due to cacti doing so well in the sun under normal circumstances.
However, this is actually a lot more common than you realize. This is one of the most common and likely answers for why a cactus would start to turn yellow.
The first thing to understand is that not all cacti are the same. Some cacti will thrive in full sunlight, but others are actually going to do better in partial shade.
People have even noted that they’ve had more issues when they purchased cacti directly from nurseries or garden centers. Sometimes these cacti that have been raised with indoor light aren’t ready to handle the harsh outdoor sunlight.
You should try to get some information about the specific type of cactus that you have. If you’re able to do this, then you can read about the recommended sunlight for the cactus and make decisions accordingly.
If the cactus has only started to yellow a bit at the top, then everything is likely going to be just fine. You can make changes to where you’re putting the cactus and it should be able to start looking healthier after some time has passed.
The Cactus Is Getting Too Wet
A cactus that is turning yellow from the bottom up is actually going to be a substantially more serious concern. You see, this is a sign that the cactus is getting too wet, and that isn’t going to be good for the plant.
You do need to water your cactus from time to time, but it really isn’t supposed to get super wet. In most circumstances, you won’t have to worry about a cactus getting too wet, but you could have made some mistakes when watering it.
Did you go overboard when watering your cactus a few times? Have you not been watering the cactus as recommended and decided to just water it as you do other plants?
If you answered yes, then it’s possible that you could be causing your cactus to rot due to watering it too much. When yellowing is coming from the bottom of the cactus and is starting to spread up to the top, it’s going to be a sign that mistakes were made.
It’s also notable that cacti can get too wet due to natural rainfall as well. If you had an unusual amount of rain in recent weeks, then that could be to blame for the cacti turning yellow from the bottom.
Those who keep their cacti outside will need to pay attention and try not to allow the cacti to get overly wet. A bit of rain is generally fine, but a monsoon isn’t going to be good for it.
If the cactus is starting to rot, then you’ll likely notice that it is becoming soft and mushy. If there are parts of the cactus that have become soft to the touch, then it’s a sign of root rot and that is very bad.
The cactus might have just been wet for too long and this caused the rot to set in. Sometimes this can happen due to being exposed to water for longer periods of time, but the soil can be to blame as well if it isn’t draining properly.
Can a Cactus Plant Be Saved From Root Rot?
Root rot is an incredibly serious problem that could easily spell the end for your cactus. Cacti that are rotting this way won’t necessarily be easy to save, and sometimes it won’t be possible to save the cactus.
Whether or not your cactus plant can be saved will depend on how bad the damage is. If the rot isn’t too severe and hasn’t spread too far, then you might be able to save things by cutting away the rotting sections of the cactus and allowing what remains to dry out properly.
When the rot is very advanced, it’s going to be far less likely that you will be able to do anything to help. At some point, the damage is just going to be too much and your cactus is likely going to die.
Just try your best to assess how the plant is doing so that you can decide how to proceed. If the cactus isn’t able to be saved, then you can take what you learned to try to do better for the next cactus that you decide to buy.
Ensure That Cacti Have Well-Draining Soil
It’s essential to take the time to plant cacti in well-draining soil so that they can thrive. You should know that cacti don’t like wet feet, and soil that retains moisture too much won’t be ideal.
If you’re worried that root rot is the issue when your cacti are turning yellow, then you should consider whether you need to alter the soil. Using better soil that drains properly might help you to avoid issues such as this in the future.
Good soil needs to be able to dry fairly fast, and this means that you should make a soil mixture that makes sense for cacti. You could buy a commercial cacti soil potting mix that will do a good job for you.
It’s also possible to make your own potting soil for cacti using a 2:1 mixture of potting mix and perlite. Coarse sand can also be handy since it can be adding to potting soil to improve overall drainage.
What If the Cactus is Rotting From the Top?
There are situations where the cactus will start rotting from the top as well. If you notice that your cactus is turning brown at the top and parts of it are becoming soft, then you might be scratching your head.
A cactus rotting from the bottom makes more sense due to water exposure and the potential for the cactus to sit in water. When this happens from the top, many cacti enthusiasts will be left wondering how it could even happen.
Tip rot isn’t as unusual as you might think, though, and it can occur for several different reasons. It could be that water has managed to penetrate some type of open wound on your cactus, and this water caused the cactus to rot at the top.
Another potential cause of tip rot involves fungal disease. The top of the cactus could have been exposed to some type of fungus, and damaged plants are going to be susceptible to fungal spores.
There have also been situations where pests have caused damage to cacti and caused them to start rotting. This could happen due to pests such as bugs trying to feed on the plant, but animals could also be to blame.
Much as with root rot, whether your cactus will survive tip rot depends on the condition of the plant. If you catch things early enough and the damage isn’t too severe, then you’ll have a chance to turn things around.
Get rid of the rotten parts of the cactus so that the rot doesn’t spread to the rest of the plant. If you’re able to do this in time, then the cactus might be able to rebound.
Sometimes repotting your cacti will cause them to turn yellow. This is basically a type of transplant shock that will temporarily cause the plants to yellow due to being repotted in new soil.
This shock and any changes in your watering schedule might cause the cactus to yellow a bit. You can avoid shocking the plant by being careful and trying to keep the watering schedule consistent.
You should also try to use a pot that isn’t a huge step up from the pot that the cactus used to be in. If you try to transplant the cactus into a very large new pot, then the shock will be more severe.
Just do your best to be careful and make good decisions and it should be fine. The yellowing should be temporary and the plant will be fine so long as you’re caring for it properly.
Exposure to Very Cold Temperatures and Frost
Many people who are keeping cacti outdoors will be living in fairly hot parts of the world. You might live in the Southwestern United States, and this should theoretically mean that you can keep cacti outside all year long.
It’s important to understand that weather changes can occur, and sometimes the temperatures can dip lower than you will expect. You might live in a climate that is normally perfect for keeping cacti outside all year round, but things could change a bit if you have a harsh winter.
Cacti won’t do well when they’re exposed to very cold temperatures, and it’s especially bad when things get moist. Sometimes you might experience a frost due to temperatures dipping below freezing briefly.
Even if that doesn’t occur, it can be bad when you have a colder and wetter winter than usual. This might make it so that your cacti will start to rot, and seeing them turn brown won’t be unusual at all in those circumstances.
If you know that the weather is going to be cold and wet, then bringing your cacti indoors will be a good idea. You can protect your cacti from frost and wet winter weather by taking them indoors, and you’ll be preventing problems from happening in the first place.
Pest infestation is a possibility that cannot be ignored, but it isn’t as common as the other things mentioned so far. Certain types of pests can be problematic for cacti, though, and it could lead to yellowing over time.
For example, spider mites have the potential to kill cacti if they manage to infect plants in large numbers. You’ll be able to recognize these bugs by looking closely and keeping an eye out for their red color.
These tiny bugs can be hard to spot sometimes, but they look like tiny red spiders and they’re well known for bothering many types of plants. Luckily, you can treat your cacti to get rid of spider mites by just using rubbing alcohol.
Spray your cacti down with rubbing alcohol and the spider mites should leave your cacti alone. It’s also wise to separate cacti that have been infested from the other plants to try to keep the mites from spreading.
Other pests to be worried about include aphids and mealybugs. Mealybugs will leave white fuzz on your cacti that will make it easy to tell that they were there.
These annoying pests will suck on cacti and cause them to become damaged over time. The damage that they cause can lead to rot in some instances.
People use rubbing alcohol spray to get rid of these pests as well, but you could also use soapy water. Handling pest issues will mostly be about spotting the problem before things get too bad.
Some people also choose to spray insecticide in the yard where they’re keeping the cacti. You could do this to try to prevent pests from bothering your plants, and it might be beneficial to more than just your cacti.
Of course, not everyone likes spraying insecticide because it could also kill beneficial insects. You’ll be able to decide what to do based on what you think is best for your property and your plants.
Sometimes Turning Brown Is Natural
There are circumstances where cacti will turn brown naturally. When some types of cacti reach a certain age, they will go through a process known as corking.
Corking occurs when a cactus begins to mature, and it will start happening at the base of the plant where it’s touching the soil. When a cactus starts corking, it’s going to have a more wood-like appearance.
Sometimes this corking will move up the plant a bit, but other times, it might just stay in one spot. It isn’t something to be worried about and the cactus should still feel firm to the touch upon inspection.
Just take the time to touch the cactus as safely as you can to see what’s going on. If everything is firm, then it’s likely that you’re looking at corking and not some type of problem.
What you want to watch out for is if the cactus turns brown and gets mushy. This isn’t natural, and it’s because the cactus is experiencing some type of rot.
You know all about rot now and what needs to be done to try to help the plant survive. Hopefully, if you’re seeing some browning toward the base of your cactus, it’s just corking and you won’t need to worry.
There are so many different reasons why cacti will start to turn yellow or brown. The most common problems are related to watering issues, and you should be able to solve things if you take the right steps to correct your mistakes.
It’s important to water cacti the right way and to avoid letting them get too wet. If you aren’t careful, then you could accidentally cause your cacti to experience root rot, and that won’t be good for any of your plants.
You can take steps to try to protect your cacti from problems such as pests to prevent damage from appearing on them. If you do your best to give your cacti the right care, then you’ll be less likely to have to deal with things such as browning or yellowing.
As noted above, some browning can be a natural part of the maturing process, but you should be able to distinguish that from serious problems easily enough. Be mindful of how dangerous excess moisture can be and try to keep your cacti safe from fungal diseases and cold snaps.
Moving forward, you’ll be a lot more knowledgeable about what you should look out for. Your experiences caring for cacti should be a lot more positive in the future.