Canning and Preserving Your Harvest

March 16, 2020
Canning and Preserving Your Harvest

If you are blessed with an overabundance of fresh fruit and vegetables, preserve your harvest for winter. Canning is one time-honored way. Here’s an overview on how to can!

NOTE: Guidelines for safe canning are always being updated so use current information. Your local county extension office has a wealth of information about canning.

  • Gather all your ingredients and equipment and make sure you have everything you need before you start. Halfway through the process is no time to be running to the store.
  • Follow recipes and directions exactly. No improvising; your family’s safety depends on doing this correctly.

The Acid Test

Is the food you are canning high or low in acid? A pH of 4.6 is the dividing line; a higher pH number means less acidity and a lower pH number means more acidity.


Low acid vegetables such as green beans or corn need to be processed at a high temperature to prevent growth of deadly botulism which thrives in an airless, low acid, moist environment. This toxin is odorless and colorless and so potent that even a minute amount can cause paralysis and death. To kill it off, low acid foods must be processed at 240 degrees—hotter than boiling water. To maintain high enough temperatures for the proper length of time you need to invest in a pressure canner. This process is not for the novice.

No Pressure

Most low acid foods can be preserved in other ways and they will not only be safer but taste better. Broccoli, corn, and green beans taste much better when frozen and have better texture. Blanch them briefly in boiling water, cool down quickly in ice water, and pack them in bags or containers for the freezer.

Put ‘Em Up!

Harmful bacteria won’t survive in high acid conditions so pickles, relishes, salsas, and tomatoes are very safe for the beginning canner. (To be on the safe side, you can add extra acidity with lemon juice or vinegar.) Jams, jellies, fruits, and tomato and fruit juices are also highly acidic. They all can be safely processed in a boiling water bath. A water bath canner is just a large deep pot with a special rack to hold 6 to 8 jars.


To avoid canning burnout, start with a small project at first. Try a few jars of salsa instead of a bushel of tomatoes. Prepare the recipe and get the water in the canner boiling.

Put A Lid On It!

Sterilize the jars and keep them hot until you are ready to fill them. Use real canning jars and new 2- piece lids. Keep the flat part of the lid hot; the screw ring needs to be clean but not hot. Fill the jars to within 1/4 inch of the top, this is called head space and can vary depending on your recipe. Wipe the jar rim and threads clean and put on the lid. Tighten it only finger tight. Place jars on the rack in the boiling water so that they are covered by at least 1 inch of water. Count processing time once the water has returned to a boil.


Most pickles need only 5 minutes in boiling water. Lift out the whole rack to remove the jars and spread them out to cool. If you hear popping noises it is the jars sealing. Once the jars are cool check the seal; the center of the lid should be depressed. If a jar doesn’t seal put it in the fridge to eat right away. The sealed jars can be labeled and stored in the pantry for winter.

The sight of those gleaming jars full of delicious food is very satisfying!

If you found this overview interesting, we’d advise that you read the USDA Complete Guide to Home Canning to make sure you read the latest on safe and effective canning!



About This Blog

Get inspired by Robin Sweetser’s backyard gardening tips and tricks. Robin has been a contributor to The Old Farmer’s Almanac and the All-Seasons Garden Guide for many years. She and her partner Tom have a small greenhouse business and also sell plants, cut flowers, and vegetables at their local Farmer’s Market.