A few of these…. Azalea, bleeding hearts, calla lily, clematis, crocus, daffodil, delphinium, foxglove, hyacinth, hydrangeas, iris, lily of the valley, lupines, morning glory, oleander, rhododendron, wisteria. And this is by no means a comprehensive list so don’t eat unless you’re positively sure it’s not poisonous!
Don’t even use non-edible flowers as a garnish, people will just assume they can eat it. I know I would!