Recipe: How to Freeze Turnips or Parsnips (re: canning parsnips)

I am sorry, but canning a low acid vegetable in a boiling water bath would be unsafe due to the risk of botulism. Unless a vegetable is pickled, it cannot safely be canned in a boiling water bath.
It is possible to process in a pressure canner, but they turn dark and get very strong in flavor. Freezing is the recommended method for preservation.

FREEZING TURNIPS OR PARSNIPS

Preparation - Select small to medium, firm turnips or parsnips that are tender and have a mild flavor. Wash, peel and cut into 1/2-inch cubes. Water blanch for 2 minutes. Cool promptly in cold water and drain. Pack into containers, leaving 1/2-inch headspace. Seal and freeze,