The local nursery has a handful of San pedros averaging 70cm high. They want to cut the cacti and destine the middle section for culinary uses and the top section for rooting.

What time of the year do you think that this is best achieved? Their goal is to have the most potent middle section (in case said potency fluctuates throughout the year), and to have the fastest/best rooting possible.

If you happen to have (or know of) some scientific evidence that backs some claim, the friend nursery will greatly appreciate it.