Too much rain for cactus

After more than a week of rain, the northeast side of several cactus started to rot.  It can be hot and dry in Austin but at average rainfall of about 23 inches a year, Austin is more than twice as wet as the typical desert environment where these plants thrive.  I think air circulation from fans would have helped but then that sort of goes against my survival of the fittest philosophy.

Then again seeing beautiful 40 year old cactuses liquify into a brown ooze isn't much fun either.  From now on, I think I will grow some desert cactus in pots where they can be more easily maintained, others I will take more effort to plant with more exposure like on the edge of a rock.