Pollan, Michael.  "Flowers of Evil," Harper's. April 1997. 
https://harpers.org/archive/2018/04/flowers-of-evil-2/

The growing of poppies  involves intent. For legal purposes, the less you know, the better. There are differing standards for why a plant is illegal:  example tobacco.

Poisonous plants some people grow:  datura and euphorbia, castor beans, and even the stems of rhubarb. 

Klein, Ezra. "Can Magic Mushrooms Heal Us?" New York Times. 18 Mar. 2021. https://www.nytimes.com/2021/03/18/opinion/oregon-psychedelic-therapy.html

Oregon is forming a board to foster the use of psilcybin for therapeutic use. The experience will be at a licensed facility under the guidance of trained professionals. The purpose is to help people with PTSD, depression, trauma and addiction.

Klein discusses the previous "model" for use of psychedelics.