Here are a couple of Earthboxes that I am growing without the usual cover, the greens because they are grown densely, to be cut at a very young and tender age and then they regrow to be harvested over and over again.
I have grown onions in earthboxes before, 20 per box. This box has 64 onions planted, and I intend to thin them and harvest them as scallions, leaving the rest to grow to full size.