Birch Tree Bed

It's going to be a heat index of 110 - 120 for the next two days. And today was our 18th day in a row in the upper 90's. No rain. Even the farmers here have gone on water restrictions. You KNOW it's bad when....

I've been giving a little attention, for the first time, to the small bed towards the back of the lawn that has 2 birch trees and a bed of day lillies. It needs some love. Things I need to do for it:

Water once in a while
Seed head the lillies so they bloom next year - done
Prune the birches to keep them healthy and let light to the lillies
Weed
Dig up, divide, and replant the lillies
Fertilize next spring

I'm trying to decide what to do with all the divided lillies. They're huge. But where do I need a new lily bed? Maybe on the back fence? But I was thinking more ramblers there. As part of the new bed on the SW corner? Make a small bed on the NE corner? Fill out the front garden, pull up a hosta or three? Just toss them or give them away? I've got no idea!