Select fully mature green peanuts. Clean and wash them.
Soak peanuts in fresh water for 1 hour, then discard the water. Cover with fresh water and soak another hour. Repeat once more, using fresh water each time, for a total soaking time of 3 hours.
Cover with fresh water, parboil for 10 minutes, and drain.
Pack hot peanuts into hot jars, leaving 1/2-inch headspace.
Prepare boiling brine using 1 cup salt per gallon of water. Cover peanuts with boiling brine, maintaining 1/2-inch headspace. Remove air bubbles, wipe rims, and apply lids.
Pressure process pints for 45 minutes or quarts for 50 minutes.
Dial-gauge pressure: 11 psi at 0–2,000 ft; 12 psi at 2,001–4,000 ft; 13 psi at 4,001–6,000 ft; 14 psi at 6,001–8,000 ft. Weighted-gauge pressure: 10 psi at 0–1,000 ft and 15 psi above 1,000 ft.