Poppy petals function to attract pollinating insects  The pollination of a poppy flower triggers the release into that flower of a substance that causes its petals to wilt within one or two days  If the flower is not pollinated, the substance will not be released and the petals will remain fresh for a week or longer, as long as the plant can nourish them
Cutting an unpollinated poppy flower from the plant triggers the release into the flower of the same substance whose release is triggered by pollination
Even if cut poppies are given all necessary nutrients, their petals will tend to wilt within a few days.