Dandelions are good, the green parts can get bitter, but the flowery bits are sweetish and also very pollen-y. I used to eat them a lot as a child. Violets are edible as well, both sweet violet and common violet. I don't remember what they taste like, but I also used to eat them as a child. Sweet violet is sometimes candied for baked goods.
Clovers are edible as well, the red clover (purple clover? Not sure) is the best in my
experience, but white is good too. I prefer using them for tea, or pulling out and eating the individual tubey flowers. They're mildly sweet.
One other flower I eat is bee balm. Its not exactly a wildflower, but it is wild other places. It tastes kind of herby to me.
Also edible (but not yummy to me) is the original and naturalized orange daylily. I have tried them but I do not like them. Another caution with these is to make sure they're orange daylilies, as I'm pretty sure only daylilies are edible. Don't quote me on that though.
As with any foraging, do your research and bring a field guide for identification if you can. Never eat anything you're not sure about.