Black Plastic
 

Tried the black plastic method and found no increase in potato production. Did stop most weeds. I cold climates help when temps are really cold does help from freezing.

I think it's mostly to stop them from getting green (less work, no hilling), and weeds. These are already big advantages. Not sure it would help against freezing, but in theory should help in spring to start growth faster.

Try clear,let’s sun warmth during day,you get some good condensation as watering.Also solarizes and kills nastys in mediums during off season.

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Plenty info in the archives