Room mate doesn't want plants around anymore...

Tell him you're bothered by something he has, and that you don't want it around anymore.. It could be a pet, toy, weird clothing, whatever.. Something that he really likes, then If he's willing to lose that thing, you may consider taking your plants to your gf.. If he really does that, you can also say "Yea but I love my plants a lot more than you love your hamster, so no Im not gonna take them away"..

i'm not gonna throw out my plants for a paranoid roomate he can leave if he's not comfortable with it. If he's a true friend he would accept that and you say you have a MMJ card tell him to stop being such a girl and man up what kind of friends do you have? None of my friends would ever dare to tell me what I can have and what I can't and alot of them do not even smoke. IMO your friend is being a little girl. "OH roomate I don't want your plants here they scare me" shut the fuck up. just keepin it real man I would not put up with his shit. It would be a different story if you were cooking meth.

If you pay half the rent there, you should be able to have what you want
in the house just as well as he should.

If I was paying rent, I'd damn well have whatever I wanted to have.
I mean, I could understand if you were a drug dealer
selling 4 oz a day why he wouldn't want the plants there. But you're not hurting anyone by having them, and he shouldn't be freaking out especially since its decriminalized.

Just talk to him. Tell him you're both adults, that both pay rent, and that you
should have the freedoms that come with having a place you're paying to
live at.

Just be an adult about the situation, tell him that you don't want to give
up such a nice investment and a hobby you enjoy doing just because he is
paranoid.

My whole thing is why in the hell is he tripping if its decriminalized?

tell him to politely fork off....alternatively poke hiim in the eye and scream NOOOOOOO I WOOONNNNNNTTTTTTT DDDDDOOOOOOOO ITTTTTTT!