Feeding Ants flowers has long been a trick of public displays. I have seen some amazing spectacles, both in big exhibits, and in the wild, of large colonies of Leaf Cutters cutting flowers and carrying them back to the nest. But beware, dont get any flowers from Florists or supermarkets. The are ALL laced with systemic insecticide and will kill the ants!
Any flowers will normally be taken, I havent come across ant that are refused.
Roses are a great favourite....
and the sight of them carrying the discs of petals is fantastic
Some displays even go to the length of stamping out shapes such as hearts at Valentines day.....
Just get your flowers from the wild, away from any possible pest control.