Unfortunately the court will decide what the shooting was over. In todays court room your guilty until proven innocent (sadly), not the other way around.u dont tell your lawyer or the courts it was over plants...it was over ur safety and ur familys...last i checked self defence is not a crime...and like u stated a good lawyer will get u out of anything...
Self defense is a very broad term, and generally speaking self defense with lethal force is very much so a crime in nearly every state. There are castle laws established in 31 states, and all of them are different. Texas is the most lenient and permits your to shoot someone on your yard to a certain degree. Florida also has very "good" castle laws, in which I personally believe they are the second best castle law state to Texas, and even in Florida you cannot just gun someone down for stealing something in your yard. In your house yes, in your yard... no. If they are in your yard when you kill them, you will have very big problems in court.
A good lawyer has a good chance of getting you out of anything, they are not guaranteed to though.
Anyone who is going to pull a trigger on someone for stealing something from their yard better think long and hard about the legal and financial repercussions. Are you going to spend $50,000 - $150,000 on a lawyer because someone was stealing a couple thousand dollars worth of plants that are completely replenishable? You're going to spend much more time in court and jail than it would ever take to grow back $150,000 worth of marijuana. It makes absolutely no sense to shoot anyone for this purpose.
I'm not trying to attack you, I'm giving you some helpful advice so that you can save a couple bucks or years.