"Did you know that you can wrap peony buds in a newspaper and put in your refrigerator

[WheelWalker]

8. Soft-tissue stems are particularly susceptible

to developing an air bubble after cutting, especially if done in the heat of the day. Think of a vascular air embolism. Cutting under water is a bit difficult and shouldn't be necessary if the plant is well hydrated to begin with, the cutting is taken early morning or evening, and is quickly placed in water. Often a cause of clone and scion failure in rooting and grafting operations in my experience.