You may want to try planting a longer storage onion. Larger and sweeter onions tend to have poor storage life because of their high water content. Try Copra, a medium size onion that stores up to a year or more under the right conditions.

Just speculating here, but eight weeks seems like a pretty long drying period and may have exposed the onions to weather or insect damage. Usually four or five weeks is sufficient to completely dry down the leaves and neck, but this varies with climate and conditions. Also store them in a cool and dry place after drying, such as a dehumidified cellar.

TomNJ/VA

Tom; Thank you. You're right about 8 weeks, I usually dry for 4 to 5, but this year I just didn't get around to it. I think the variety (unknown) is OK, it's small and yellow; I've been using it for about 15 years; it's bulk from our local feed and seed store, and has worked so far. What about the heavy spring/early summer rain? And something I forgot, most of the onions are double-hearted, although I harvested piecemeal once the necks were soft and/or the leaves were lying down. Any thoughts? Regards, Peter.

I think it was the weather rather than your curing practices. It rained and rained here, too, which caused the exact symptoms you describe on my White Wing onions, which was my best variety in 2012. Milano, a blocky red onion from Johnny's, cured well and is holding up in storage, at least for now, and does not have the same problem.

The weather may be a factor - if the onions have a high water content they do not store as well. Re the double centers, this is from: http://www.caes.uga.edu/Publications/pubDetail.cfm?pk_ID=7749

"Onions are prone to physiological disorders that growers should try to minimize. One such disorder is splits or doubles. This condition is caused by cultural and environmental factors as well as being influenced by genetics. Over-fertilization, uneven watering, and temperature fluctuations (particularly below 20 degrees F) are all believed to influence double formation. Some varieties are more prone to production of doubles than others. Varieties prone to doubling should be seeded a week or so later on the plant beds as well as transplanted a bit later to minimize this disorder."

This site also has lots of good information:

http://www.extension.umn.edu/distribution/cropsystems/DC7060.html

We also had record spring rains here in southwest Virginia, and my large Ailsa Craig onions only lasted a month, but they are known for this. Likewise for Walla Walla, although I expected a bit longer from them. So far my Candy and Copra are still tight and hard, and hopefully the Copra will carry until next years crop. Once a variety starts to sprout I mince them in a food processor and freeze them.

TomNJ/VA

Tom and Planatus: Thank you both, As to double centers, it might well have been the rain also. I don't fertilize, just 1/2 inch of compost every fall, but I guess one can have too much of a good thing. Regards, Peter.