Ginger is harvested in winter and will decline in quality over time, so it may be best to harvest and use sooner rather than later. It will help with the side effects of meat stored for harsh and long times
Nutmeg is harvested in August and then proceeds through processing routes that may take enough time to complete and be ready for use by winter
Cinnamon is largely harvested after monsoon season June-December, so will be available for use in time for fall and winter time

[–] villasv@beehaw.org 4 points 11 months ago

So the very basic solution to the mystery is that winter foods are those that are usually harvested to be eaten during winter :-|

[–] myfavouritename@beehaw.org 1 points 11 months ago (1 children)

I don't think the author was trying to say that these spices are harvested in the fall and enjoyed in the winter. In fact, I think they are clearly saying the opposite.

Just as cranberries’ fall harvest makes them a natural choice for Thanksgiving, I thought that perhaps the seasonality of spice harvest had something to do with their use during the winter months. However, this doesn’t appear to be the case.

And

Take ginger...The plants can be harvested at any time of year if they are mature and haven’t been exposed to cold or wind.

Or, if they are trying to make that point, they are doing so in a way that includes contradictory details.