As hard as it may be, let it go man.
Karma always has a way of catching up with people, more so if seeking revenge. You can always grow another plant, you can't get back years of your life if he rats you out. As previously stated, if they rip, they rat.
It's easy to say go kick his ass, but in all reality, that's the kind of shit that will hinder legality. Honestly, think about it, would you legit fuck someone up over a tomato plant? A plant is a plant. I would get pissed, but I would just brush it off and move on. Besides. Didn't you say you're a father? Worst case scenario, say he rats, and where does that leave your kids? I have a family of my own, I have shut down because of a security issue soley because their livelyhood depended on me, and me alone. You gotta weigh what's important, and act accordingly.
I'm not being a dick, I'm just telling you my perspective.
Cheers
Keystone