I pulled out my onions today to dry because most of the tops were turning brown. I planted onion sets as usual but these onions look weird. Many of them are split on the bottom where the whiskers grow and some have what look like small onions starting to grow in the crack. Why are they doing this? I called my mom who gardened for many years and always planted lots of onions. She was stumped as well because she said hers had never done anything like that. Any ideas?
Keep in mind, JoJo, that those "whiskers" are actually the onion roots.
The "bulb" is the base of the leaves. So, what makes leaves grow? And, grow and grow? Well, I'd say nitrogen.
Perhaps they had an abundance of nitrogen and maybe a little too fresh. They tried to bulb-up and stop growing because "it was their time" as determined by the sun up in the sky. But, growing got away from them, they split and tried to grow some more. . . .
Another guess is if the ground dried out and then the plants received an abundance of water.