If it can be naturally grown it is banned because you cannot have a patent on it and everyone could grow it freely. So what do they do?

Make it illegal.

Now, if the drug was made in a laboratory and can have a patent then its ok because big pharma can solely be the only ones to profit. Big pharma doesn't want nature robbing it's profits. Big pharma ultimately is in the biz to make money not make you healthy. What a shit ass world we live in... $$$>Health