How do I know when my onions have cured?

[Community Table Garden]

I harvested my Sweet yellow onions about three weeks ago and they have been curing in my shaded greenhouse under fans. Most of the foliage on the onions has completely dried up, and they all look great, but how do I know if they are done curing? Should I cut the dried up foliage all down?
The picture is from a few weeks ago

 

[Meadowlark]

In curing for storage you want to reduce moisture content as low as you can. I do this by withholding water a few days before harvest and then pulling the onions and letting them dry in the sun for a couple of days.

After drying, I use scissors to remove all but about 1 inch of the tops. Yours should be dry enough to remove the tops and put in storage.