Many of you have asked me, “Why does a brown spot on cactus appear?” well, the cactus you have just purchased or even the one you have been caring for a long time might suffer from a disease called cactus brown spots. You might get worried and have tried many solutions, yet you get no result.
Brown spots on cacti can be a sign of several deeper issues, such as pest infestations, improper temperature, and root rot. You can maintain the health and vitality of your cactus plants by understanding the causes and implementing suitable cures and preventive measures.
In this article, provided by the theHplants team, we will discuss the reasons for brown spots on cactus plants and how to overcome them from A to Z. Read this post to the end and follow its tips, and we guarantee that there will be no more brown spots on your plant, and you will have a fresh and healthy cactus. Don’t forget to share this article with whoever has the same problem. Also, we talked about browning of leaves tips in a separate article, which I suggest you read.
Reasons for brown spots on cactus plant:
When you get a new cactus, the first thing you need to do is to provide proper soil for it. Good soil will bring good growth. After taking care of the soil, you need to examine all the situations to determine the main reason for the brown spot on the cactus.
Cactus browning does not mean that your plant will die, but you should take it seriously. This problem originates from different reasons; for example, if the browning starts in the upper parts of the cactus, it can be due to sunburn. On the other hand, if the lower parts of the cactus start getting brown, it might result from root rot.
We can classify the reasons for brown spots on cactus plant as follow:
- Root rot: This might happen due to overwatering or fungal diseases
- Pests and blights: These little creatures, like ticks, can hurt your cactus.
- cold: Exposing the plant to the cold is also a factor in losing the freshness of the plant
- heat: Heat can dry the thick tissues of the cactus and then turn its stem brown
Root rot
When cacti’s roots are exposed to too much moisture, a disease known as root rot develops, which causes decline and limits the plant’s ability to absorb water and nutrients. Some symptoms include a bad smell, fragile roots, yellowing, wilting, and delayed growth. In order to treat root rot, take out the cactus, clip the afflicted roots, allow them to dry, repot in soil that drains properly, and adjust watering techniques to stop it from happening again. Using the right soil, watering carefully, making sure drainage is good, avoiding humid conditions, and keeping an eye out for disease or stress indicators are all part of prevention. The best way to eliminate the causal agent of the disease is to use a fungicide.
Pests and blights
Cacti are severely endangered by pests and blights, which can result in brown spots and an overall decrease in health. Common pests that destroy cacti and encourage fungal infections are mealybugs and scale insects, which feed on the tissues of cacti. In addition, overwatering or improper drainage can lead to blights like bacterial soft rot, which causes black spots and mushy blisters on the cactus. To get rid of the blights and pests, first, you need to examine the cactus to determine the blight type, then use a proper pesticide. So, you can use an insecticide to deal with blights. Washing the insect and blight with a weak washing solution is another way to eliminate them. Also, you can use cotton soaked in oil to eliminate these insects and blights. This will create an oily layer on the top of the plant that cuts off the oxygen supply to the insects; over time, the insects will die. You should know that if the browning of the cactus is in the form of small spots on the new parts of the plant, it can be caused by tick; to overcome this, you can use miticide.
Cold and heat
Both heat and cold can significantly impact Cacti. Severe cold can cause frost damage, which makes the cactus’ tissues freeze and leave blackened or discoloured spots on it. However, too much heat can result in sunburn, which causes the damaged parts to turn brown or white. Cacti must be shielded from harsh weather conditions by having enough insulation during cold snaps and shade during hot days to avoid sunburn and heatstroke. In order to ensure the health and well-being of cacti under a variety of weather situations, regular monitoring and appropriate environmental condition adjustments are essential.
Too much direct sunlight
The next reason for the brown spot on the cactus is sunburn. In this case, brown spots appear on the top of the plant. You may wonder, aren’t cacti resistant to sunlight? But you should know that not all types of cacti grow well under sunlight. Some types of them need minimum sunlight and partial shade to grow. Cactus or any other plant that you buy and move to a new place will face some stress. Because the plant enters a new environment with a lot of light from an environment with ideal conditions, there is a possibility of the plant getting sunburned due to this change. It should be noted that if the cactus is exposed to a lot of light for a long time, the light can cause red to purple spots. These spots are due to the fact that under environmental stress, the defence mechanism of the cactus plant is activated and produces substances that lead to the production of this colour.
In most cases, sunburn spots are white at the early stages; if you neglect them and do not seek treatment, they will turn brown. This type of problem is common among cacti, and there is almost nothing we can do about it. However, if your plant has whitish spots, you can save it by moving it to a shady area.
Natural ageing
Finally, browning and hardening the cactus body shell from the bottom can be a natural process resulting from cactus ageing. However, you should observe all the above-mentioned tips and examine the plant well; after ensuring there is no blight, conclude that the plant is old. Remember that your cactus pot should not be too big or too small. A bigger pot will keep more water inside, which can hurt the roots.
How to get rid of spot on brown cactus?
As we mentioned earlier, if the browning starts from the bottom of the plants, the reason might be fungal diseases, so the first thing you need to do is to reduce the watering and then use a fungicide, as the instruction says. After using a fungicide, check the pot, ensure the drainage system is working well, and control the watering; note that overwatering can cause severe damage. To find the perfect time for watering, check the soil; if 1/3 of it is dry, it’s time to water your cactus.
Should I cut off the brown parts of the cactus?
Once a cactus starts rotting, you have to remove all the rotten parts from the plant to slow down the spread and destruction of the plant; if these things are not cut, your plant will be destroyed.
Are all brown spots on cacti harmful?
Not every brown spot on a cactus is dangerous. Certain brown patches might just be natural and not a sign of any serious health issues. But it’s crucial to keep a constant eye on the cactus and recognize the difference between spots caused by pests, diseases, or environmental stressors and those that are harmless. The general health and look of the cactus can be preserved with regular care and routine inspection.
Are chemical treatments safe for cacti?
Yes, when applied carefully and in accordance with instructions, chemical treatments can be safe for cacti. It’s crucial to use solutions made especially for succulents and cacti and to follow dose and application recommendations. It’s important to employ caution and only administer chemical treatments when necessary to properly handle pests or diseases while limiting any potential risks to the plants, as overuse or incorrect use of chemicals can kill cacti.
Getting rid of brown spot on cactus using fungicide
The best way to eliminate the causal agent of the disease is to use a fungicide. After that, you can cut out the damaged parts using a sterile and sharp knife. Then add the Sulfur powder to the wounds to help the plant heal.
The place where you put your cactus is essential, do not expose it to cold or heat, such as next to a heater, etc.
Blight and brown marks on cactus
To get rid of the blights and pests, first, you need to examine the cactus to figure out the type of the blight, then use a proper pesticide. . . So, you can use an insecticide to deal with blights. Washing the insect and blight with a weak washing solution is another way to eliminate them. Also, you can use cotton soaked in oil to get rid of these insects and blights. This will create an oily layer on the top of the plant that cuts off the oxygen supply to the insects; over time, the insect will die. You should know that if the Browning of the cactus is in the form of small spots on the new parts of the plant, it can be caused by tick; to overcome this you can use tickicide
Finally, Browning and hardening of the cactus body shell from the bottom can be a pretty natural process resulting from cactus aging. However, you should observe all the above-mentioned tips and examine the plant well; after ensuring there is no blight, conclude that the plant is old.
Remember that your cactus pot should not be too big or too small. A bigger pot will keep more water inside, which can hurt the roots.
How do you fix brown spots on cactus?
Brown spots on cactus are mainly caused by sunburn, root rot disease, corking, or overwatering. To fix the discoloration, allow the soil to dry out between waterings. Be sure to move your plants to a place with filtered light, and if your apartment plant has root rot, treat it with a fungicide.
Conclusion spots on cactus
We covered the reasons for brown spots on cacti and how to overcome this problem. As mentioned above, Brown spots on cactus are mainly caused by sunburn, root rot disease, or overwatering. To fix the discolouration, allow the soil to dry out between watering. Be sure to move your plants to a place with filtered light, and if your plant has root rot, treat it with a fungicide. You can keep your cactus healthy by understanding the problem and implementing the mentioned solutions.
This article has been reviewed by Tibor Janda.
very informative !