You completely neglect to mention the massive EMP effects which would, in effect, eliminate electricity globally and cause the instant collapse of society completely apart from any of the kinetic damage and fallout.
Rhubarb springs to mind, grows well in cool climates and denying sunlight produces a better crop.
Any others?
Edit: the book recommends stocking up on rice, beans & grains.
The collapse would not only be instant, but within days there would be mass starvation and chaos.
From the description at the top of the thread it's as if we'll just come out of our shelters after a week and everything will go back to normal, we'll just drive down to Arby's for dinner, maybe catch a movie.
More people need to watch Threads.