Subject: 5 foot San Pedro Cactus (echinopsis pachanoi). approx 4.5" in diamater.
What I Did: While repotting, I allowed it to fall. approx 6 inches from top, the poor cactus has a cut which penetrates about half the way through. The upper and lower interior cut surfaces has a 1/4" gap. I taped the injured section in a way that (I hoped) would pull the surfaces together, and perhaps heal itself. Removed tape after 2 weeks, and no dice. the upper and lower surfaces are still 1/4 inches apart, and calloused over.
Remove the top part, allow it to callouse over, then stick it in the same pot if there is room and it will regrow roots becoming a new plant,
the lower parent part will dry out at the cut and probable in several months, grow a new baby from that area, if it doesn't then it will continue to grow anyway. in the desert, animals and insects cause damage to the plants and they survive so try not to worry.
Next time you want to handle the plants, fold a sheet of newspaper or soft kitchen paper and use it to wrap around the plants for protection as you work.
Best regards, WeeNel
I think WeeNel's is the best course, but I can relate a different experience. In 1971 we were rescuing and transplanting a 5 foot saguaro - Carnegiea gigantea - when it received a gash from the truck's tailgate. We didn't think it had much hope because the gash was maybe 18 inches long. We just planted it and left it. Then we moved.
I got to see it again 40 years on --- and there was the scar, with the saguaro itself being now about 20 feet tall!
As WeeNel said, the cactus are built for staying alive in the desert.