I planted some red onion and sweet onion sets (small onion bulbs) on March 3rd.

I thought that when the tops fell over and started turning brown, they would be ready to harvest. The green 'stalks' are still standing BUT they are developing flower buds.

I read another thread here, but didn't really understand the response.

What does this mean? I am in NC, and these are 2 months in the ground.

What should I expect? Did I do something incorrectly? Thanks in advance for advice/info.