I successfully grew the bottom of a store bought to seed. This will be my first attempt, learning curve.
The 4x8 was $20. I couldn’t not get it.
Discussion
Bruh that is highway robbery. Mine isn’t near as nice as that one but it’ll hold dirt
The trick with onions is getting them in the ground as early as you can in your season, and choosing the right day-length varieties for your location. Onions start to bulb when the number of hours of daylight reaches a certain point (the actual number is determined by the genetics of the variety), so getting them in the ground and growing as far as possible before the days get that long is key to getting nice big onions.
The seeds came from a white onion from the store. I have no idea what variety