How to save a rotting cactus?

Is your favorite cactus or succulent rotting? Don’t worry, we’ve all been there, sometimes there is nothing you could have done to avoid it, and today we will go over exactly what rot is and how you could save your plant if you are able to catch the onset of rot early on.

What is rot?

Rot on cacti and succulents is caused by a fungal infection that attacks the skin or the root system of a plant. If not addressed quickly, rot will work its way into the plant’s vascular bundle (veins traveling up and down the center of the plant), and eventually infect the entire plant.

How do I know if my cactus is rotting?

Any darkening of the skin should be carefully inspected daily. If the affected area grows or if the plant exhibits any softness, it should be treated in order to prevent any further spread which will kill the plant. It is important to note here, that cacti can exhibit light softness dues to dehydration and this is completely normal. Softness related to rot is usually accompanied by darker skin and is so severe you will feel the skin will almost want to rip when pressed.

Treatment.

Once you have identified that a plant has rot, you want to remove it from your grow area as soon as possible to avoid contaminating your other plants. Then, grab a sharp blade and clean it thoroughly with rubbing alcohol. Cut away all of the rot until you see no dark or orange tissue, and quickly apply sulfur plant fungicide on the cut to avoid any further fungal infection. Always treat in the evening when the sun is not too strong, and place treated plants in 50% filtered sunlight for 2-3 weeks or until the cut has been calloused and becomes firm. Make sure to check on treated plants for any further softening or discoloration as fungal infections may persist if any rotted tissue was left behind.

How can I avoid cactus root and surface rot?

Many factors have an effect on rot and fungal diseases in cacti and succulents. Mainly: soil, light, and ventilation must be adequate in order to prevent root and skin rot. The soil must be mainly inorganic, your plants should receive 8-10 hours of unobstructed (lightly-filtered) solar exposure per day, and there should be enough space around your plants for proper airflow (or fans should be introduced).

I hope this short guide and video on rot and its eradication was useful to you, and hopefully, you were able to save a plant or two!