Q. Is there any way to separate the babies from the mother cactus when they are joined along the stem or do you just let them grow?
A. Yes, you can separate the baby cacti, or the pups, from the mother cactus even if they are growing along its trunk. However, I would let them grow. They are quite interesting in a landscape when they are allowed to grow more naturally.
The easiest cacti and succulents to separate are those which produce what we call “offsets” or sometimes we call them “pups”. Offsets are pups that are produced separately from the mother plant, usually on short rhizomes. The rhizome is cut which separates the pup from the mother cactus. The pup then is totally on its own and will send down its own roots and establish itself.
Pups are any “baby cactus” or succulent whether it is an offset or attached directly at the stem. When pups are attached directly to the stem they can be separated from the mother plant with a sharp, sterilized knife.
The pup is allowed to “heal”for several days in a warm environment without any direct sunlight. This healing produces callus tissue which protects both plants from dehydration and diseases.
Once the healing has finished, the pup is placed on top of soil with extremely good drainage where it can root. The soil is moistened about every three weeks during this time. No rooting hormone is necessary.
This may not be the same cactus, but you can get an idea of what it might do.
it can add a very interesting element to your landscape if left alone.