Onion roots are shallow, so keep the soil evenly moist. If the soil becomes too dry, the onions will form bulbs pre- maturely, resulting in small bulbs.
Onions need to breathe and should not be stored in a plastic bag, which is often how you carry them out of the store.
Spread the onions out in a single layer, taking care not to bump or bruise them. As the onions are curing, their necks will gradually wither and the papery skins will tighten around the bulbs.
Onions typically require 55 to 65 days from sowing to transplanting in the field under ideal growing conditions.