Taking and Rooting Cuttings

Sometimes you may buy an unrooted cutting. You may also want to cut off a column to propagate, or need to take a cut due to rot, disease, instability, or wind.

If you can choose when to take a cut, try to do it when the weather is nice - taking a cut during very wet or cold conditions can increase chances of infection. When cutting, sterilize the knife with alcohol before and after each cut to prevent spreading disease. If you're cutting rot away, inspect the inside of the cut and if there are dark or discolored parts of the inner flesh, resterilize and cut more. I recommend chamfering the top side of cuts or cutting at an angle - as it dries, the wet flesh will shrink in, and a flat cut will turn into a bowl shape that will hold water and lead to rot. Immediately after cutting while the ends are still wet you can optionally apply powdered sulphur to the cut end to protect from disease and rot, and/or apply powdered rooting hormone to the side that will be rooted which can greatly speed the rooting process. Let cuttings callous by putting them somewhere in shade, dry, with good airflow. In front of a fan can do the job quickly. After about two weeks there should be a light tan scab over the cut, then it's ready to try to root. If you purchased a cutting, it should have arrived calloused and none of the above should apply.

Rooting is tied both to growing temperature range and also to moisture exposure. The idea is to tease roots out with some very light water exposure but not to let the end sit soggy or damp for long which will rot it. There are a few ways to do it - you can put it cut end down in some porous inorganic, very lightly water it every so often. You can set the cut on top of some mixed substrate and stake the cut up - you wouldn't want to water it much using this method. Or you could just plant it in a permanent pot and soil mix and water it extremely sparingly for a long time. It's safe to withhold all water until you see the column start to shrivel or wrinkle, at which time it's fine to give it a little. If it's rooted you may see it plump a bit which would indicate its roots are taking up water. I don't recommend burying cuts too deeply because the more green flesh below the surface, the higher the chances of rot.