I read that using a vase that was short and squat to hold a fair amount of water helps. Since water high up on the stem deteriorates the stem. I have a weird little vase like affair that has a cluster of pins in the bottom that the stem sticks on and it seems to keep the flowers fresh longer, but maybe it is the low level of water in the short squat container. It looks like a flying saucer with a hole in it where the stems go. Just a though.