This is sometimes referred to as double dormancy. Seeds with morpho-physiological dormancy require both warm and cold ...

Poppies bring a delightful, delicate look to any garden with their tissue-like petals in spring. You'll be shocked to learn this is the best time to plant them.

Yet the accumulated palaeoclimate data from the polar twins seems to argue for the opposite response, with stronger stratification in cold climates, not warm ones. One would tend to put more faith ...