The ideal time is spring and summer.
The soil layering technique takes more time and it is cumbersome. That is bending the stem in to the soil in another pot. Put some rocks for weights.
Propagation chamber technic is easy and one can do dozen or more at a time.
I also do it when it is the time to cut back the jasmines if they are over grown. This time I propagated on September 20th.They are rooted now, but I will wait for another 2-3 weeks.
It works 95% of the time. My failures are with Tindora (gentlemen’s toes-Donda- Ivory gourd) now. But I will succeed in spring.
I have grow lamps and my jasmines are blooming now also.