It's suppose to get down to 33 tonight...

do I need to cover my lilies? What about peonies? I think everything else is pretty hardy or will regrow.

No beaker, you should be fine. Mine had already sprouted a month ago or so and it got to 27 and absolutely nothing on the lilies was hurt. Most of the peonies had budded and I lost only a couple flowers.

Too late. I rushed home and covered everything. I used every sheet and towel I owned and ran out. Someone remind me I need to buy sheets when the white sales start up. LOL, I had to take stuff out of the laundry and stole the towels on the dog and cat chairs. I then switched to pots. I'd rather be safe than sorry. I have way too much invested in lilies to lose them to a cold snap. I did lose all my tulips one year that were just beginning to bloom. It was very disappointing.

If it gets to mid 20's you might be in trouble. I have lots of lilies too so I can relate. But as long as you're above freezing there should be nothing to worry about. Sometimes towels make it worse as the plants bend under the weight of the towel and the frost that may get on it, or they stick. Good luck - I hope you fare OK!