One occasionally sees, cut into the side of a hill or lying flat next to a home's foundation, a door in that ground that leads to a drab, potato-colored wonderland of vegetable storage: a root cellar.

Knapp, who runs Offbeet Farm in Fairbanks, Alaska, debuts with a comprehensive manual on how to harvest, process, and store beets, kale, potatoes, and several other hardy vegetables so they can be ...