We get random crops in the garden all the time. Last year it was a whole bunch of romaine lettuce that popped up from where a lettuce plant that had gone to seed had been placed after being pulled up. The seeds wintered over and as I was prepping the garden in the spring I found a whole bed of lettuce sprouted and flourishing. Surprise!
I tried scattering seeds last fall on purpose and didn't get anything in the spring this year. Gardens are funny that way, eh?