• Wash the potatoes thoroughly and peel them. Trim away any damaged areas. NCHFP's tested method calls for peeled potatoes.
• Cut potatoes into approximately ½-inch cubes. Place them in an ascorbic acid solution while you work if desired to help prevent darkening.
• Drain the potatoes. Place them in a large pot of boiling water and boil for 2 minutes, then drain again.
• If using salt, add 1 teaspoon canning or pickling salt to each quart jar. Salt is optional and is used for flavor rather than preservation.
• Pack the hot potatoes into hot canning jars.
• Cover the potatoes with fresh boiling water, leaving 1 inch of headspace. Do not use the water the potatoes were precooked in because it contains excess starch.
• Remove air bubbles, adjust the headspace back to 1 inch if necessary, wipe the jar rims, and apply lids and bands according to the lid manufacturer's directions.
• Place the jars in a pressure canner and process pints for 35 minutes or quarts for 40 minutes, using the correct pressure for your altitude and type of canner. Potatoes are a low-acid vegetable and should not be processed in a boiling-water bath.
• Once processing is complete, turn off the heat and allow the pressure canner to depressurize naturally. Do not force-cool the canner.
• Remove the jars according to your canner manufacturer's instructions and allow them to cool undisturbed. Check the seals before labeling and storing.

Pressure & Altitude Adjustments

• For a dial-gauge pressure canner, process pints for 35 minutes or quarts for 40 minutes at:

  11 PSI from 0–2,000 feet

  12 PSI from 2,001–4,000 feet

  13 PSI from 4,001–6,000 feet

  14 PSI from 6,001–8,000 feet.
• For a weighted-gauge pressure canner, process at:

  10 PSI from 0–1,000 feet

  15 PSI above 1,000 feet

  using the same 35-minute pint or 40-minute quart processing time.