Probably because:

A) The onions are popular
B) The stores buyers are stupid
C) Most customers have no idea of the importance of day length
D) They bought them in bulk at a cheap price

My local supermarket was selling their own brand of 20W-50 motor oil in the winter as "All Season"! Just rampant ignorance and apathy.

TomNJ

I plant Granex 33 onion plants in late November and December. I wonder, is there is any part of the country where Granex 33 would be planted in April?

People do buy them and then wonder why they don't bulb up like store bought Vidalia onions. Bonnie plants sold Yellow Granex for years as Vidalia onions, The Georgia Department of Agriculture put a stop to that, Vidalia Onions is a registered trademark. Short day onions are designed for winter growing. Texas probably grows more of this type than Georgia, they just can't call them Vidalias.

i always thought granex was a short day onion and as such would fail to produce a bulb in philly.

vidalia onions are very sweet because the georgia soil in vadalia county has very low sulfur content and it is sulfur compounds that make alliums hot and store longer. vadalias store just 30 or 60 days due to the lack of sulfur.

tom