All jack by the hedge near me gats sprayed with herbacide, it doesn't kill it, it just makes it go yellow and removes the compatition. I have eaten daffodil flowers, but only the 6 outer petals, don't know if the flowers have the toxins in though (good practice is to check before eating, but i am a muppet). I am going try and get mahonia flowers when doing the school run, if they are got just as they are opening they taste like lemon curd with brussel sprout, wierd but nice.