I would have to say you will have to make those type of arrangements and keep them where someone can find them upon death. What your wish are so they will be carried out as you planned or buy a prepaid funeral plan at a funeral home and discuss your service with them can be done and its cheaper...
so the best thing is to plant them got you I found an herb store and the bad part about it is this week Im relocating to Cali San Diego so I am going to have to research out there should there be any one in San Diego area that would be interested in meeting up for a talk or some herb shopping...