Pull one up and find out. Sorry but that's about the only way to tell. My guess is yes. But even if the white part isn't, the greens can be used.

Rodney

Almost surely yes. They never really get fibrous.

The stems of the flower heads can be tasty too. Just pick them when young and tender. Mine were a little hot to eat directly off the plant but they were great, chopped up for soup or an omelet.

For years I planted a few store bought green onions in the back of a border just for the flowers. The underground parts were frequently different from year to year. Seems produce people sell a variety. The parts below ground are sometimes quite good to eat.

Edible ? Sure 100%.
But when gone to flower, the bulbs will be small wit a core in the middle. Still good for fresh eating but not a keeper.