Your Yard and Garden

OK, I am new hear and looking for help.  I live in Kentucky and I thought we were past our last point of frost, with easter just around the corner.  Yesterday it was 83 (and has been for a while) and now it is 37 degrees, with a freeze expected every night for the next 5 nights or so.  Sat Low will be 19 degrees!

I worked in my garden last week for probably 6 or 7 hours.  Planting different plants, moving some around and cleaning things out.  I am not worried about the stuff I planted since they are all still in the ground.  However I have ALOT of stuff blooming and growing all ready.  I am going to cover as much as I can up, however I can't get everything, my flower gardens are just too big.  Which ones are most at risk:

1.  Hostas - not worried about

2. Shrubs - not worried about

3.  Ferns 

4.  Azealeas

5.  Rhodadendrums

6.  Many varieties of lilys (tiger, toad, easter, day, ect)

7.  Black eyed susans

8.  Ornamental grasses

9.  Roses

Lots of others that I don't even know the names of.

Is there a list anywhere that shows plants that are in danger in frost?  Does anyone know which plants are in danger??  I need help fast!

I also have a pond with lily pads already at the surface!