Baskets of Gold Alyssum
I decided on just the creeping phlox and candy tuft to accompany my tulips. Of course they are always small when they first go in, but I suspect they will spread quite quickly out there on the north sunny side of the house.
Just remember when you are wondering what is in bloom at any particular time of the year, talk a walk and spy on the neighbors gardens! Then head straight to your local garden center and ask for the same thing!