Q Why are stored onions rotting?

A Onions need to be fully ripened to store well. It’s also important that the bulbs have a thin neck as these store better. When they stop growing, in August or September, lift them, dry them and ripen them in warm, dry conditions before storing. If you have to harvest them in wet weather, if they have a thick neck, or if they can’t be dried fully, use them straight away. Or, chop and freeze them instead of storing them as bulbs.