My onions got frozen in garden then thawed..can I harvest and freeze then store?
You can, but these are pretty hardy, and will continue to grow just fine if you leave them. With a layer of straw mulch, you can extend the harvest. Depending on your variety... (the spicier the onion, the more sulfuric acid is present.) The sulphuric acid content of the onion can act as an "antifreeze", and even though they may sustain some damage, they will certainly not die from this.