If you're talking the old fashioned Grandmother's flower Garden made with 1 to 2" hexes then anything goes. Most I've seen use light colored solid for the paths between the flowers and pretty much anything and everything else for the flowers. Mine is yellow. It has yellow paths and the centers of the flowers are the same yellow. The flowers are all different with two rings of different fabrics around each flower. They're a great scrappy pattern.
Rodney