Got extra summer squash? If you’re like most homesteaders, you probably do. These vegetables grow prolifically, and it’s not hard to find yourself inundated with more zucchini, butternut squash, summer squash, or winter squash than you know what to do with. While many people choose to dehydrate or freeze their squash, canning is a great way to save freezer and cupboard space. Canning is an easy way to produce a long-lasting supply of this delicious crop, as canned foods last over a year in most cases.
Zucchini and other squashes must be canned using a pressure canner. Water bath canners only reach boiling point temperatures, while pressure canners heat contents to 240 degrees Fahrenheit. Any low-acid foods, like most vegetables, meats, and seafood, must be canned using a pressure canner to avoid the risk of contracting botulism or other foodborne illnesses. If you don’t own a pressure canner, don’t risk it—just go ahead and freeze your leftover squash.
Keep in mind that if you are looking for crisp, crunchy squash, canning may not be your best option for all varieties. Freezing will work better, for example, for vegetables like summer squash. When you place sliced or cubed squash into a jar, it can become overly soggy and also affect the heating pattern in the jar. While spiralized zucchini, butternut squash, and winter squash all can quite nicely, it’s worth being willing to experiment with your canning recipes to obtain the proper ratios. Whatever doesn’t work well with canning can be frozen, pickled, or dehydrated.
Here’s a super easy way to can summer squash and zucchini using the raw pack method…
- Clean and sterilize your jars
I either wash the jars in the dishwasher, or in hot, soapy water. Then, I place them in the oven and heat them at 250 degrees. I let them stay hot there while I prepare everything else. You will also want to sterilize your lids and bands, even if you’re using brand new bands (you should NEVER reuse lids, as the seal won’t be as effective).
To do this, simply bring some hot water to a boil on the stovetop and drop in both the lids and bands. Then, bring the heat to a simmer. This will also help you keep them hot while you’re preparing the jars and ingredients.
- Prepare your ingredients
Bring a large pot of water to a boil. While it’s heating up, you can wash the squash, scrubbing it with a vegetable brush to get it extra clean. Cut the ends off and peel if you prefer it that way. You can then cut the squash into whatever shapes or sizes you need.
The best options are as thick rounds about half an inch thick, or into cubes. You can also spiralize or shred your ingredients, depending on how you plan to use them later on. Whatever you do, don’t mash the ingredients before canning. Tests have proven that there are density issues with mashed squash that can prevent adequate heat distribution.
You may choose to blanch the squash before canning as well. This will help preserve some of its freshness, but is not a required step. If you decide to do this, simply dip the squash for two minutes in boiling water.
- Fill the jars
Pack the slices into hot jars, leaving about an inch of headspace. You can add salt if you prefer, but this is not required. Don’t add more than half of a teaspoon for pints or a teaspoon for quarts, as it will become overly salty over time.
- Finish the jars
Pour boiling water over the squash, making sure to maintain that inch of headspace. To remove air bubbles, press with a wooden spoon or tap the jar gently on the counter. Then, wipe the rim of the jars with a clean, damp cloth, and place the lids and bands on the jars.
- Process the jars
You should process your squash at 10 lbs pressure weighted gauge, or 11 lbs for a dial gauge. If you are canning at a higher altitude, you will need to adjust accordingly. A full canner of pint jars will take around fifty-five minutes, while one of quarts will take about ninety minutes. Make sure your canner is maintaining adequate pressure during this time.
Once the time has elapsed, wait for the canner to stabilize back to a neutral pressure before removing the lid. Trying to remove the jars before the pressure has equalized can be dangerous. You can always just let the cans cool in the canner along with the water.
- Let the jars cool
Place the jars on clean towels to cool and seal. Try to set them out away from a breeze, as this can cause the jars to crack. You may hear popping noises as the lids seal.
- Store the jars
Canned squash will store for several months on end. Signs of spoiled jars include mold or discoloration, although some white residue atop the jars is a normal byproduct of canning. You can simply wipe it away.
Then sit back and admire your pretty little jars!
Update 4/17/13– Since first writing this article about two years ago, and after having a chance to use my canned squash, here are my thoughts…
- The squash was saltier than I would have liked. If I can them again, I will omit the salt. (Salt is added for flavoring, not for preservation.)
- The squash made really nice pureed baby food.
- I realized we don’t really eat squash much… at all. Since I don’t have a baby eating pureed foods anymore, I probably won’t can squash this year.
- We definitely prefer fresh squash and zucchini to canned.
Note: The National Center For Home Preservation has put out this statement about canning squash…
Recommendations for canning summer squashes, including zucchini, that appeared in former editions of So Easy to Preserve or USDA bulletins have been withdrawn due to uncertainty about the determination of processing times. Squashes are low-acid vegetables and require pressure canning for a known period of time that will destroy the bacteria that cause botulism. Documentation for the previous processing times cannot be found, and reports that are available do not support the old process. Slices or cubes of cooked summer squash will get quite soft and pack tightly into the jars. The amount of squash filled into a jar will affect the heating pattern in that jar. It is best to freeze summer squashes or pickle them for canning, but they may also be dried.
You might also like…
- Sauteed Squash and Onions
- How To Can Squash Pickles (Pickled Squash Recipe)
- How To Freeze Shredded Zucchini for Quick Breads
- Moist Homemade Zucchini Bread
updated 05/26/2018 by Rebekah White