Not something that I have encountered. You might try to match the symptoms with pest and disease guides. http://www.omafra.gov.on.ca/english/crops/facts/95-063.htm http://www.essentialgardenguide.com/garden-vegetables-problems/11/Onion/

That is so odd. It's almost like they just completely dried out and rotted inside.

Given the leaves in the photos I'd suspect Fusarium basal rot as the most likely of the common allium fungus diseases. Pull a couple of them and look for dark pink-brown colored roots and/or white fungus growth at the base of the bulb.

Given the wet cooler weather this spring fungus diseases seem to be increased and wide spread.

Dave

To be fair to Dixondale, I would suggest you contact them with pictures and describe the issue you are having. They have a huge vested interest in any problems associated with their products as that is their livelihood. Just my thought.

I agree and will contact Dixondale. I have used their onion plants for some ten years and don't believe the plants were the cause. I'll report what they say.

Tom

I agree with Dave that it sounds like the basal rot. If you determine that is what it is then you'll want to avoid planting alliums in that bed for a few years. I've had Botrytis neck rot once on garlic but that doesn't typically manifest itself until at or after harvest.

My Copra onions from Dixondale had a higher rate of 'failing to thrive' after planting out then did the Candy , Red Candy, Superstar, or 1015Y but at least 80% are doing well. The rest just never developed any new leaves after transplant which may be due to a few nights around 20f in March.

That actually looks like a burn. Was there herbicide in the grass clippings?