Canning Blueberries

Canning blueberries is a simple way to hold onto a summer harvest that always seems to vanish too fast, tucking whole berries into jars so you can spoon them over pancakes, stir them into oatmeal, or fold them into a winter cobbler long after the bushes have gone bare.

There is something satisfying about opening a jar of whole blueberries in the middle of winter and having them look almost exactly the way they did going in. Packed in a light syrup, they hold their shape and color on the shelf, and they are ready to go straight onto a bowl of yogurt or into a batch of muffins.

Blueberries are a high-acid fruit, which means they can be safely canned in a water bath canner without any added lemon juice or other acid. That also means the sugar is entirely up to you. The syrup here is about flavor, color, and helping the berries keep their shape, not about preservation, so you can lean sweeter or lighter (or skip the sugar and use juice or water) without changing whether the jars are safe to put on the shelf. If the idea of canning without a heap of sugar is new to you, I get into it more in my post on whether sugar is necessary for preservation.

If you end up with more berries than you can pack whole, they also turn into blueberry jam, blueberry syrup, blueberry butter, or blueberry pie filling, and you will find all of those and more in my roundup of blueberry canning recipes.

Choosing Blueberries for Canning

The nicest canned blueberries start with firm, ripe berries that are dry and evenly colored, with no soft or leaky spots. Slightly underripe berries actually hold their shape a little better in the jar than very soft, dead-ripe ones, so if you are picking or sorting specifically for canning, err toward berries that are plump and firm rather than the softest ones in the basket. Give them a good look and pull out any that are shriveled, mushy, or showing mold, since one broken-down berry will cloud the syrup around it.

Cultivated blueberries and wild (or lowbush) blueberries both can beautifully, though wild berries are smaller and pack even more tightly into the jar. Frozen blueberries work too, which is handy if you buy in bulk or freeze your own harvest and want to can a batch later in the year.

If canning frozen blueberries, they fall apart a bit more and end up closer to blueberry compote, but that’s no less delicious.

Ingredients for Canning Blueberries

The ingredient list here is short, which is part of the appeal. You need berries, and you need a liquid to cover them, and that is really it. Everything past the berries is a choice about how sweet you want the finished jars to be.

• Blueberries: Fresh or frozen, firm and ripe, washed and picked over. Plan on roughly 2 pounds of berries per quart jar, or about 1 pound per pint, which works out to around 8 pounds for a canner load of 9 pints and about 12 pounds for 7 quarts. Wild or cultivated both work.
• Sugar: For the syrup. Granulated white sugar is standard, and the amount is up to you. A medium syrup suits most berries, but a light or very light syrup keeps things closer to the fruit’s own sweetness. The sugar is for flavor, color, and shape, not for safety, so any of these strengths is fine, and you can leave it out entirely. Maple and honey work well as sweeteners too.
• Water: The base of the syrup, heated together with the sugar. If you would rather skip the syrup, you can cover the berries with unsweetened white grape juice, apple juice, or plain water instead, and the jars are just as safe. Unsweetened blueberry juice is another option if you happen to have some on hand.

Because blueberries are naturally acidic, you will notice there is no bottled lemon juice or other acid on this list. That is expected, and it is one of the ways this recipe differs from something like tomato canning recipes, which require acidification in every jar for safe canning. The berries bring their own acidity, and the water bath process time does the rest.

Making a Sugar Syrup for Blueberries

Canning syrup is nothing more than sugar dissolved in water, and you choose the strength based on how sweet you like your fruit. For blueberries, a medium syrup is the usual pick, made by heating about 5-1/4 cups of water with 2-1/4 cups of sugar for a 9-pint load, or 8-1/4 cups of water with 3-3/4 cups of sugar for a 7-quart load.

If you prefer less sugar, a light syrup uses roughly 5-3/4 cups of water to 1-1/2 cups of sugar for pints, and a very light syrup (which comes closest to the berries’ natural sweetness) uses about 6-1/2 cups of water to 3/4 cup of sugar. You do not have to use every drop, so it is fine to make a little extra and set the rest aside.

To make it, combine the sugar and water in a saucepan and heat, stirring, until the sugar dissolves and the mixture comes to a gentle boil. Keep it hot while you fill your jars. If you would rather cut the sugar without cutting all of it, a mild honey or a light corn syrup can stand in for up to half the table sugar. And if you would like to skip sugar altogether, just heat plain water or unsweetened juice to a boil and use that as your covering liquid instead.

I have a printable table that covers all the syrups for canning fruit, from extra light all the way to extra heavy, so take your pick.

How to Can Blueberries

Blueberries do especially well as a raw pack, which simply means you put the raw berries straight into the jars and pour hot syrup over them. Raw packing keeps the berries whole and firm, so they look their nicest in the jar, and it is the method I choose for almost every time. I will walk through the raw pack first, then cover the hot pack option in case you want to fit a few more berries into each jar.

The whole process is quick once your jars and canner are ready, so it helps to have everything set up before you start filling. There are really only two decisions to make here, which covering liquid you want (a syrup at whatever strength suits you, or juice, or water) and whether you are raw packing or hot packing, and both come down to preference rather than safety. The steps below cover prepping the fruit, filling the jars, and then processing.

Prep the Berries and Jars

Start by getting your water bath canner heating and your jars washed and warm, so everything is ready when the berries are. Wash the blueberries a quart or two at a time under cool running water, then drain them well and pick through to remove any stems, leaves, or berries that are soft, split, or underripe. Working in smaller batches keeps you from crushing the berries at the bottom under the weight of the whole harvest.

Have your covering liquid hot and ready, whether that is a medium syrup, unsweetened juice, or plain water. It helps to add about 1/2 cup of the hot liquid to the bottom of each clean jar before you add any berries, which keeps the berries from packing into a dry clump and helps cut down on floating once they are processed.

Raw Pack the Jars

With that splash of hot liquid already in each jar, fill the jars with raw blueberries, shaking each jar gently as you go so the berries settle and nestle together without needing to be pressed down. A wide canning funnel makes this a lot tidier, since blueberries love to bounce and roll. Fill them up to within about an inch of the rim so you have room for the syrup.

Pour the hot syrup, juice, or water over the berries, covering them completely and leaving 1/2 inch of headspace at the top of the jar. Run a bubble tool or a thin plastic spatula around the inside of the jar to release trapped air, then check your headspace again and top off with a little more liquid if needed. Wipe the rims clean with a damp cloth, center the lids, and screw the bands on until they are fingertip tight.

Hot Pack Option

If you would rather fit more berries into each jar, you can hot pack them instead. Blueberries shrink when pre-blanched, so you’ll get fuller jars, but softer fruit out of the canner.

To do hot pack, heat the blueberries in boiling water for about 30 seconds and then drain them before filling the jars. The quick heating softens the berries just enough that they settle down and pack more tightly, so you tend to fit a bit more fruit per jar and see less floating after processing.

The trade-off is that heated berries are more fragile, so a few more of them will burst and break apart as you pack and process, which makes for a softer, more sauce-like jar. Fill the hot berries into jars, cover with your hot liquid to the same 1/2-inch headspace, and finish the jars the same way.

Because the berries are already warm, the hot pack processes for the same time as the raw pack for pints, and slightly less time for quarts, so check the altitude chart below for your jar size.

Canning Blueberries in a Water Bath

Once your jars are filled and lidded, lower them into the simmering water in your water bath canner, making sure they are covered by at least an inch of water. Bring the canner up to a full rolling boil before you start counting your processing time, and keep it at a steady boil the whole time. A steam canner works here as well, following the same times.

For a raw pack, process pints for 15 minutes and quarts for 20 minutes at sea level, adjusting the time upward for altitude as shown below.

When the time is up, turn off the heat, remove the lid, and let the jars sit in the canner for 5 minutes before lifting them out. Set them on a towel to cool, undisturbed, for 12 to 24 hours, then check that the lids have sealed before labeling and storing them.

Tips for Success

Floating berries are the most common thing people worry about, and they are almost always a cosmetic issue rather than a safety one. Raw-packed fruit is lighter than the syrup around it, so it tends to rise toward the top of the jar as it cools, leaving a layer of liquid at the bottom. Adding that splash of liquid to the jar before the berries, packing the berries snugly, and not overheating the syrup all help, but a little floating is normal, and the jars are perfectly good to eat.

The other thing worth mentioning is color. Blueberries can tint their syrup a deep purple, and sometimes the berries closest to the lid look a little pale or faded after a few months on the shelf. That is a normal storage change and does not mean anything is wrong. Storing the jars somewhere cool and dark slows it down and keeps the color looking its nicest for longer.

Ways to Use Canned Blueberries

Canned blueberries are ready to use straight from the jar, drained or not depending on what you are making. Spoon them, syrup and all, over pancakes, waffles, French toast, oatmeal, or a bowl of yogurt or ice cream. Drained, they fold right into muffin and quick-bread batter, pancake batter, or a coffee cake, and they save you the step of thawing frozen berries.

They also cook down quickly into a warm sauce or compote for cheesecake and pound cake, and a jar is a nice head start on a cobbler or crisp when you do not feel like starting from scratch. If you find yourself using them mostly for baking, you might also like keeping a few jars of thickened blueberry pie filling on hand, which goes straight into a crust with no extra work.

Here are a few of the questions that come up most often about canning blueberries.

Canning Blueberries FAQs

For more ideas using this summer berry, take a look at these blueberry canning recipes.

Blueberry Canning Recipes

Blueberry Jam (without Added Pectin)

Canning Blueberry Lemonade Concentrate

Canning Blueberry Pie Filling

Looking for more fruit to put up this season? Here are more fruit canning recipes to try.

Fruit Canning Recipes

Canning Strawberry Lemonade Concentrate

Canning Lemonade (& Lemonade Concentrate)

Canning Strawberry Pie Filling