I Need To Master All The Plants. For Some Reason I Gain Healing Skills When I Study The Plant Near The Dry Grass Is that Normal? And When Do I Know When It Is Mastered?

You need to watch for a message about mastering the plant the first time a villager studies a plant. After that, all of the special plants increase healing skill when they are studied.

Thanks, I Thought I Never Master The Plants <(^^<)