Rosemary is easy to propagate, and sometimes roots will develop even in a glass of water on a sunny windowsill. I have found that the best time of year to take cuttings is in the late fall and early winter.
I actually managed to get a 3 foot tree growing from an avocado seed but we moved and I lost it. Gotta start over. Apparently though, from what I researched, growing a tree from an avocado won’t yield avocados the same way avocado farms do.