If your crime novel or short story is going to feature a poison, then research is vital. Apparently, around 1800 more than 90% of poisoning cases were caused by toxic plants; nowadays, they account for about 7%. Many sources conflict regarding toxicity so seek out more than one reference, if possible.
Some plant poisons are quickly fatal, like oleander or Jericho rose, Barbados nut, banewort, moonseed, muskrat weed, jimsonweed, lily of the valley, monkshood and rhododendron, for example.
If your villain plans to kill a victim with a toxic plant, then the taste needs to be disguised. As you would guess, salads are popular, as are casseroles – though bear in mind that cooking may reduce the effectiveness of the poison.
Our garden contained many aloes, which are liable to poke out your eye if you’re not careful. We decided to remove them for the sake of our grandchildren. Other resident plants are oleanders, which are staying, even though they’re considered to be ‘the most dangerous flowers on earth’. With that kind of comment, you’ll appreciate that caution is called for with regard to these evergreen colourful bushes. In Italy it’s used as a funeral plant – just make sure the funeral isn’t yours or a loved one’s.
Oleander - Wikipedia commons
The oleander is found almost anywhere. On the central reservations of our dual carriageways here in Spain, it provides splashes of colour – red, white and pink blossoms. Once it takes hold, it requires little watering.
All parts of the plant, including the nectar of the flower, are poisonous. So is the smoke from burning the plant; and even the water in which it may be placed. The poison contains cardiac glycosides, oldendrin and nerioside.
The poison acts immediately; it is a cardiac stimulator, causing sweating, vomiting, bloody diarrhoea, unconsciousness, respiratory paralysis, and death.
Recommended treatment is prompt vomiting and to quickly seek medical aid.
Like many poisonous substances, they possess beneficial properties too. Extracts of oleander have been employed in the treatment of leprosy. In Europe the plant has been used as a rat poison.
It has also been used as an abortifacient, and as a means of suicide. In Sanskrit the plant’s name means ‘Horse Killer’; in Arabic and Italian, ‘Ass Killer’. Goats, however, seem immune! Moral: treat this plant with respect, don’t be an ass and horse around with it…