Answer: To harvest onions for storage, watch for when the tops begin to turn yellow and fall over. The bulbs should be in the two- to four-inch range. At that point you may wish to bend the foliage flat to the ground to speed up the maturing process. After about three weeks, or when the tops are totally dried up, dig them up. (Do not harvest when the soil is very wet, and be sure to harvest before the first frost.)
Harvest on a dry, sunny day and lay the onions out to dry for an hour or so in the sun. Brush off any excess soil, then cure them by placing them in a single layer in the shade for about ten days. If conditions are inappropriate for outdoor drying, you may have to spread them out on the floor indoors under a fan. Finally, clip off the tops about an inch from the bulb and store in a cool dry place. Storage onion varieties will keep from 4-12 months when properly dried and stored.
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