Here are several threads that have discussed Lily of the Valley as a method:
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1] -- [
2] -- [
3] -- [
4] -- [
5] -- [
6].
Yesterday, I wrote a
lengthy post explaining what you need to be mindful of when selecting plants for CTB & why fatal dosages have so much variance. As such,
I only recommend plant-based methods if you have a personal reason for choosing them over SN, inert gas, or Night-Night methods - all of which are well-documented on this forum & in scientific research (by comparison).
Plant deaths aren't peaceful, painless, or quick. Their toxins are an evolutionary adaptation to ensure survival and reproduction. The average person or animal wouldn't eat poisonous berries again if it made them sick for a week.
Take this from someone who also prefers natural, "undetectable" methods. My family, particularly my mom, will go on a conspiracy witchhunt if I CTB by SN. There is no alternate explanation for a SN death - cyanosis due to methemoglobinemia turns your skin blue/gray & the presence of SN can be confirmed in an autopsy/lab panel.
Last year, I attempted using ~50 aconitum seeds, which I have previously discussed on this forum. Regardless of your chosen plant, you are unlikely to succeed unless you consume
a lot (in my case, 200+ seeds as they were small), at which point you may require antiemetics & other medications depending on your symptoms.
To be clear, I'm not discouraging plant-based methods, but you have to do additional research and prepare in excess if you want some semblance of a peaceful death. There are a lot of unknowns - even scientists don't fully understand the mechanism of action for plant toxins.