extracting pyretins from Tajets sp. (cempasuchil, flor de muertos)

Hi, I have plenty cempasuchil flowers left over from día de muertos (day of the death) and although I don´t need it now, I am curious about a way to extract insecticides from them. Any recepi?

Pyrethrum is a rather nasty neurotoxin which kills pretty indiscriminately.
It's still legal for organic growers to use it here, but it won't be for long...

Hi,

the flowers must be dried and then crushed and mixed with water.