Learning Draenor Herbalism
You can learn Draenor Herbalism from the scroll [A Compendium of the Herbs of Draenor]. You will get this scroll by picking any herb at Draenor. (100% drop chance)
1 - 100
If you have the [Sky Golem] mount, you should use it while leveling herbalism because you can pick herbs without dismounting.
You can level to 100 in any of these zones below, there is not much difference between them.