How deep are you planting them? Too deep and they won't bulb up. They also like a good amount of nitrogen.

I am having the same issue this year (first year trying onions). I planted sprouts in the spring (march) and they are now falling over. Largest onions are a little bigger than a golf ball.

From what I have now read, I think I should have planted these in the fall. Not sure if I should just harvest these, or leave them till next year (assuming the start growing again in the fall).

I planted them around three inches deep and I always supplement with fertilizers and still have the problem. And Scotty66 thats a garlic not an onion.

When onion tops die back it means they're done and should be dug. You might have planted the wrong variety for your zone.

Here is a link that might be useful: Onion day length map

definitely check out your distance from the equator and white kind of onions will do well for you. A good catalog will tell which which latitudes each variety will work for.

Also, if your onions send up a flower/seed pod in the middle, clip this a couple inches from the base so that the plant puts more energy into the bulb instead of making seeds.

And Scotty66 may well be talking about fall planting onions since he is in Texas.

Oh -- and are you planting seeds, sets or plants? Seeds do best planted in the fall in warm zones. I always have great luck with plants -- they bulb up better than sets for me. (I'm in zone 5 because of altitude, not latitude, so I can't use long day onions.)

hope this helps!

Three inches deep is too deep. The onion wants to bulb with most of the bulb out of the ground and only its roots in the ground. Somewhere in time, onions got mislabled as root crops, but that bulb is actually a swollen leaf base. One inch deep is sufficient. Also, nitrogen is good for making bigger onions. And I agree that you need to check out what type you are growing and if it is appropriate for your area. Dying back at the beginning of summer sounds like a short day type. I'd try to make a guess where you are based on your zone, but 6a-7b makes no sense to me... Cheers!

I'm in the 8 zone but they were sweet red onions sold in sets by bonnie co. and they never made a flower or a seed pod at all.

If this is what you bought http://bonnieplants.com/products/vegetables/onions/sweet-red-onion it says it's a short day onion which is right for your zone. It also says it's a transplant, not a set.

That would be the Red Grano. Normally a nice size onion, so I think that narrows it to too deep planting. You transplant them shallow so that the top of the bulblet is a bove the soil. It must grow above the soil, bury it and it will not form up.
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Too deep may be causing them too rot too which could explain them dying off early.

yep, mine were sweet red onion sets from bonnie that I bought at home depot. I thought I planted mine only 1" deep. I just pulled a bunch and most were 2" round with half the bulb out of ground. tops had completely fallen over.

Guess I'll try seeds in the fall.

Yeah, I realized last year that I had to be careful about side dressing with composted manure because I buried some too deep that way. They grew alright but it left their skins in bad condition. This year I'm trying less, more often. So far so good.

I pulled mine.... a pretty sad bunch (bur aromatic)
I pulled the one garlic, just to see how they were doing

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