Purchasing plants from Rastafarians

There is no harm in purchasing plants from the Rastafarians. Generally, it is permissible to buy and sell plants, hence there is no harm in purchasing normal plants from them. Yes, if they are selling plants that are used for intoxication, then purchasing such plants with the intention of attaining pleasure therefrom (by smoking or consuming it) will not be permitted. If the plants are purchased for medicinal use, then they will only be permitted if a Halaal alternative is not available and there is certainty that one will be cured by using the plant. The treatment must be prescribed by a pious Muslim doctor.