Question
QUESTION: Hi Greg,
I am new cactus enthusiast. I purchase two golden barrel, 10" each. Unfortunately one of them suffered from root rot. I have done the remedial surgery as advised on various websites.

I have also read that there is a kind of rot which starts from the top. So could you please advise me as to how to prevent such rots. I know one way is to water less. But I am interested in knowing weather it could be good idea to spray the plant and the soil mix with standard fungicides like Bavistine/mencozeb.
ANSWER: There are really only 2 things that will cause rot, too much water and damage to the plant (caused by frost, sunburn, or insect damage). Echinocactus grusonii doesn't like a lot of water in winter, but no matter what time of year, always let the soil dry between waterings. It also doesn't like extreme heat, so if your in a place like Phoenix AZ, afternoon shade is best. Hope this helps.

Sincerely,

Greg

---------- FOLLOW-UP ----------

QUESTION: Greg, Thanks for the advise and surely it is helpful to me. I would take care not to damage the plant, in perticular. But I hope you understand that despite all the caution that one may observe, it is always possible that the plant gets damaged or overwatered. Is there no way to provide even a week form of imminity by fungicide treatment. Has this been known to be harmful?

Answer
I don't think it would be harmful, but I worry about the fungus becoming resistant to the fungicide. It happens with bacteria and I don't know if it would happen with a fungus. If you had the last of a species that needed to survive to preserve the species, I would say use it.

But you have one of the most popular plant around that seem to be available everywhere (although not cheaply). Just like humans, some plants might be more susceptible to attack or infection. But I don't think it will hurt, so you can try it. Good luck!

Sincerely,

Greg