Poultry Talk Ontario (pto.ca)

Day 1 Jan 31/16

Started my hopefully giant onions today
Using Alsia Craig exhibition seeds
Prepared spot in garden last fall for them in spring
We grow about 300-400 onions but these will be my babies till end of July when we see how we did
Had a couple approach 3lbs last year but I think I can hit 6 or 7 lbs
We will see how it goes

Do you follow Dan aka Allotment Diary on Youtube? He's been documenting his attempts at a 10 lbs onion for a few seasons... even got some seed from a 3rd place onion from a fair/show a few years ago, that one was 13 lbs!!! I guess growing conditions are different in the UK, might not be of use to you.
Good luck. : )

thanks for that I'm going to check it out
last year was my first year trying but didn't put much effort into it lol
my biggest was 3lbs
but already hit first snag this year as our 16mth old sawyer got ahold of it and decided he needed to shake them
and now it looks like only 2 seedling will start from this batch instead of the 40 I was going for

Ok, sorry, I HAD to post this cute man with his onion. : ) Half an ounce shy of 18 lbs!!!!!!!

I came across this video of a grower way up north who does the huge veggie thing...his secret is the compost tea....some of these are ridiculously sized...maybe some ideas for your onion project?

I am setting up a new compost tea approach this year...focusing on a mix of my normal manure and greens compost half and half with a hardwood mulch compost...from what I have been reading, I was getting the good bacterias, just not so much the good fungal side of the spectrum...which the hardwood mulch compost will provide.

With the root systems on an onion being so small and shallow, I wonder if they would benefit greatly from mycorrhizal fungi supplements? It would allow the small root system to intake many more nutrients. We used this technique on some fruit trees and pumpkins with amazing results...it fosters a great symbiotic relationship which helps the roots draw more nutrients in, and also makes more of them that were previously unavailable to the plant reachable. Might be worth a test on a few of them to see. Mycorrhizal fungi supplements are available at most garden centres.

compost tea works wonders. I use old pantyhose and a aquarium aerator stone and a 5 gallon pail,
I think that's a great idea with the mycorrhizal fungi, I use it on a lot of stuff but didn't cross my mind for the onions