Thanks all. That is what I thought. They are already yanked. and is dinner tonight.I had one flower in the whole scad of onion sets so not bad. The onions are fairly small since I never give them the room they deserve because my garden is only 20' x 16' and between trees..

Kevin, Like Landscraper says, it does depend on quite a few things. For storage onions, generally if you see a full sized onion at the base they are getting close. Next, check the neck of the plant just above the onion bulb. When the onions are finishing up this part gets soft and the tops start to flop over. If it's still firm, you have some time yet. When it does soften, stop watering and plan on harvesting within a few weeks. If you do a google search on "when to harvest onions" you'll get a ton more info and some pictures too.

I have not waited for mine to completely go brown, mostly because I am eager to use the spot for transplanting something else. It sounds like you will have to stagger your harvest. Your question actually does not come up that often, and the answer is not as straightforward as I would have thought. http://forums.gardenweb.com/forums/load/allium/msg0720492514944.html is a thread started six years ago that has excellent advice. My favorite answer is the first response in the thread linked below (http://forums.gardenweb.com/forums/load/allium/msg0712253021698.html) It would be nice to hear more experiences. Best of Luck! Here is a link that might be useful: http://forums.gardenweb.com/forums/load/allium/msg0712253021698.html

I'd harvest the onions now, and you could have been pulling and using them since they developed their round shape. Mine I harvested in September when the tops died back. You don't want to let them get frost damage since they then would not keep well. Pull them and spread them where they will be protected from temperature extremes and will get dry enough to store. When dry, cut off the tops and the roots. Depending on what type you grew, they may only stay useable for a few weeks (mild ones like Ailsa Craig or Walla Walla) or until March or so if they are specifically storage varieties. Regardless, when mine start thinking about sprouting, I make French Onion Soup, which also freezes well, to use up the remainder. Since yours are still growing, you may not have gotten a variety that is specifically bred for shorter northern season use. Brussel sprouts are supposed to be improved by frost, but you can certainly harvest them now. I am not fond of them, though so have no experience growing them.