sometime in the recent past Omelet posted this:
In article ,
Wilson wrote:

I know that I can buy seeds (not talking about onion sets), but I've got two
onions that have produced nice 3" flower heads that seem to still be
blooming. What I'm wondering is how long should the flower heads be kept for
the seed to viable? I mean should the flowers all die and the head change
color or what? The flowers right now are such a light green as to almost be
blue.
TIA

Until the pods are dry.

I get chives coming back from seeds every year and they spread from the
pots to the ground because I did not gather all the seeds. ;-)
That may be so(w), Omelet, the re-seeding part that is. But it appears that
"The chive is a bulb-forming herbaceous *perennial* plant." So whether or
not you gathered all the seeds, the plant would come back year after year.

I have a small clump of chives, never gather the seeds and the clump changes
little in size from year to year.

Happy gardening! Been a cold, slow, damp summer here - still waiting for a
red tomato ;-)

--
Wilson N44º39" W67º12"