Onions are typically cool-weather loving plants. Down here I plant them in late winter and they will be ready to pull in late spring or early summer. I have also planted them in the late summer and harvested in early winter. I've never tried to grow them over the winter months though. The garlic takes up nearly all of the space but I always keep a little space for onions and lettuces. Onions, like garlic, does best in well-draining soil.
