I think this is Allium stellatum.
Also known as wild garlic but I've read the bulb is more like an onion.
Allium stellatum (Autumn onion, Prairie onion) is a perennial wild onion native to North America, where it grows in rocky, sandy soil. It grows from a bulb to about 1-2 feet (30-60 cm) with tufts of leaves which die back as the scape of pink to purple flowers forms. The bulbs are strongly flavored but can be eaten.