[mumofstig]

You can only grow from seed if you have somewhere to grow them til March - if not it has to be sets!

[Nobbie]

I've always had great crops from sets, with the exception of the reds which always seem to bolt. I'm trying seed this year to get some red onions and also to get some longer storing onions. It is a lot more effort though, but all good fun. I think with onions, I grow them so I don't have to buy them, so if they didn't bolt and stored better I'd stick with sets.

[devonbarmygardener]

I've always grown a successful summer crop from sets.
Autumn planting sets I've found to be a waste of time so far.

This year I've been persuaded to try onions from seed so I'm taking up the challenge!

[sowitgrowit]

Onions from seed for the first time for me, this year.  Since our allotment is mostly about saving money, I'm keen to have a go at something that can give me 400-odd onions from a 99p pack of seed!

[Mattgregory27]

This will be my first full year on the plot and I will be trying both seeds and sets and seeing what works best for me. I think it is just nice that I can get a pack of seeds out straight after Christmas and get something going!! 

[New shoot]

That's what I like about seeds as well Matt    Its just nice to have them on the windowsill and then later on, out in the greenhouse, when not a lot else is going on 

If you have the room/growing conditions/inclination to try seeds, there are a few advantages.  I grew both sets and seeds last year.  Quite a few set grown ones bolted, but not a single seed grown one.  The seed grown ones also grew bigger and out performed the set grown ones by far.

As others have said, the choice of varieties from seed is great and as I usually pick my onion seeds up in the 50p seed sales, they are an inexpensive crop to grow 

[al78]

You can only grow from seed if you have somewhere to grow them til March - if not it has to be sets!

You can sow direct outdoors in March as well.

[jaydig]

I've tried both sets and seed, and I seem to have more success with seed in that I don't get so many bolting. I have used heat treated sets and still have a problem with some of them bolting.

[Trillium]

I've also used both over the years, and find seeds work best for me. Mind, I must get them started very early so they're a good size for planting out time.