Q.Issue With A Recently-purchased Balloon Cactus.
Dear Madam, Sir, As the proud owner of 10 different varieties of cacti (see my Photo #1), I have a question regarding my most recent one, a Balloon Cactus (see my Photo #2), that I have just repotted, 20 days after purchasing it. Because I didn’t have my glasses with me at the time of purchase, I later had the unpleasant surprise of discovering what seems to be a fungus infection, that I have already tried to deal with by spraying small quantities of insecticidal soap (1%) & neem oil (1%) diluted in filtered water. So I’m wondering what kind of treatment might be able to preserve the remaining 90% of my plant which is pretty healthy, such as performing a surgical cut without making things worse. Any expert advice you may have would therefore be most appreciated. Kind regards.
Certified GKH Gardening Expert
Without knowing the exact fungus, a generalized approach is necessary. You can try applying a copper fungicide to stop the fungal infection. You may opt to cut out the lesion but that opens up the cactus to more pathogens. It is easier to do with cacti leaves. These articles should help you decide:
https://extension.arizona.edu/sites/extension.arizona.edu/files/pubs/az1399.pdf
https://www.gardeningknowhow.com/ornamental/cacti-succulents/scgen/cactus-anthracnose-control.htm
https://www.gardeningknowhow.com/ornamental/cacti-succulents/scgen/fungal-lesions-on-cactus.htm
