Question about skills please`

I just got the skill Botanist. I have the 99 phials but what do I do. Just walk up to a plant and if it has a powder to extract it will automatically extract it? Cause I walked up to quite a few plants (the ones Overcloud9 showed in her walk through) and pressed the 'enter' button and nothing happens. So am I doing it correctly? I only have the Expert in this skill. Also I have the skill Loot for Grom but it's grayed out, is it still active even though it's grayed out? Any help would be appreciated thank you.
Katie
Katie