Hey, since the leaves spawn in Venore, obviously you can drag them around through the main continent (Thais, Carlin, Ab'dendriel, Venore). But it's also worth noticing that you can get the same leave in a cave west of Edron, so you can also put them in houses in Edron and Cormaya if you'd like.
Here is where to find them:
Three or four of them are respawning there in some of the bigger caves!
- No, it's not possible to put them in your backpack
- No, you can't bring them to Oramond
- What is more, you can bring them to Port Hope (and any other city to which you can manually push them). Here is a yt video explaining it: https://www.youtube.com/watch?v=_VVkrbVsWgo