Pick through the peanuts and discard any broken shells. Give the peanuts a good wash.
Place in the slow cooker along with the salt.
Pour the water so that it covers at least two inches above the peanuts (but don't fill the slow cooker to the brim or it will overflow).
Cook on high for 5-7 hours. Peanuts should be soft but not mushy. Taste-test a few at the 5 hour mark and if they are crunchy, cook longer.
Notes
What’s the difference between raw peanuts and green peanuts?Raw peanuts have been air dried to allow them to be shelf stable. This makes them easily available no matter the time of year. Green peanuts are fresh out of the ground and are only available in season, so they’re often not in the stores. Green peanuts do not have to be cooked as long, so if you are able to get them, reduce the cooking time by almost half.