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Preserve the best of summer’s bounty to enjoy all year long with this easy blueberry jam recipe! The homemade jam is perfect on toast, stirred into yogurt, spooned over ice cream, dolloped on pancakes, or shared with friends for the holidays.
Blueberry Jam Homemade
I’ve been making this homemade blueberry jam recipe for years, because the same thing happens each season: I take the kids to a nearby farm to pick blueberries for a couple of hours, and we inevitably come home with more fresh fruit than we can possibly eat at once. When this happened again last week, I turned to my favorite recipe as a simple way to preserve our harvest. After all, we can only consume so many batches of Blueberry Muffins or Blueberry Scones in one week!
Ingredients for Blueberry Jam
This is just a quick overview of the ingredients that you’ll need for a batch of homemade blueberry jam. As always, specific measurements and step-by-step instructions are included in the printable recipe box at the bottom of the post.
- Blueberries: only use fresh, ripe blueberries for this recipe. They will have the best acidity and tannins to give the jam a more complex flavor, and the skins will be the proper texture. Frozen blueberries tend to be mushier and more watery than fresh fruit when thawed, which will likely alter the consistency of your jam.
- Lemon juice: you won’t actually taste the lemon in the jam. Instead, the lemon juice serves a very specific purpose. The lemon juice lowers the pH of the jam, which neutralizes negative charges on the strands of pectin and helps your jam set.
- Granulated sugar: I know that 8 cups sounds like a lot of sugar, but trust me: you need all of it! Stick with regular granulated sugar (instead of sugar substitutes like Splenda or stevia) and do not decrease the quantity called for in the recipe. Jam making is an exact science, so measuring the correct quantities of fruit, sugar and pectin are essential to a successful batch of jam.
- Butter: this ingredient is optional. You can’t taste the butter in the final product; however, it does serve a specific purpose. As you heat the berries, the proteins open up into strands that get tangled up and help stabilize the bubbles into a foam. Adding the butter (a fat) helps to prevent this tangling, and therefore reduces the amount of foam on top of your jam.
- Powdered fruit pectin: pectin is a natural fiber found in plant cell walls, and most concentrated in the skin of fruits. It is water-soluble and binds with sugar and fruit acid to form a gel. The pectin is a necessary ingredient in this recipe, as it helps the jam set properly. The pectin also shortens the cooking time, resulting in a fresher blueberry flavor. Do not substitute with liquid pectin, as the two are not interchangeable.
Equipment Needed for this Blueberry Jam Canning Recipe
Here are some helpful tools to get ready before you start making the jam.
- 12 sterilized half-pint mason jars and lids: this recipe yields about 11-12 cups of jam, so you can use any size jars that you prefer (or a combination) to accommodate this amount. I like half-pint jars because it’s just the right amount of jam to keep in the fridge after it’s opened.
- A sterilized funnel: this makes it easier to get the jam inside the jar without spilling; however, it’s fine if you don’t have a funnel — you can carefully spoon the jam into the jars instead.
- Tongs: these canning tongs are incredibly helpful when taking the jars in and out of the boiling water.
- Saucepan: for cooking the berries. Allow plenty of room for the berries to boil, bubble, and foam!
- Canner or Large Pot for Boiling Jars: this needs to be very deep so that you can cover the jars with at least 1-2 inches of water. I use my deepest stock pot for this step, since I don’t have an official canner to process the jars.
- Mixing bowl
- Potato masher or food processor: to smash the berries before cooking
- Wooden spoon
How to Sterilize Jars and Lids for Jam
It’s a good practice to sterilize the jars and lids before canning in order to kill any bacteria, fungi or yeasts before filling. There are a variety of ways to sterilize the jars (here’s a helpful article with different options). I typically use the dishwasher, and make sure that the jars and lids stay hot in the machine until I’m ready to fill them.
How to Make Blueberry Jam from Scratch
This recipe is incredibly simple — it’s just important to get all of your ingredients and equipment prepared in advance because the process moves quickly. In less than 45 minutes, you can have an entire batch (12 jars!) of homemade blueberry jam canned and ready for the pantry. There’s nothing more satisfying than hearing that “pop” as the lids seal!
- Crush the Blueberries. I use a potato masher to squish my berries, but you can also pulse a few times in a food processor if that’s easier. Just don’t puree the fruit — you want some texture to the berries since they will continue to cook down on the stovetop.
- Combine Blueberries, Lemon Juice, Butter and Pectin. Place the crushed blueberries, lemon juice, butter and pectin in a large Dutch oven or saucepan.
- Boil. Bring the blueberry mixture to full rolling boil, stirring constantly.
- Add Sugar. As soon as the mixture boils, stir in the sugar. Return to a full rolling boil and boil exactly 1 minute, stirring constantly.
- Fill Jars. Remove the berries from the heat, skim off the foam, and quickly ladle the jam into hot jars. Add the lids and rings.
- Process Jars in Boiling Water. Set the hot jars on a rack in a canner or in a large pot of boiling water. Boil for 10 minutes.
- Cool. Place the jars on a towel or rack to cool overnight.
How to Serve Blueberry Jam
This homemade blueberry jam is delicious spread on toast, dolloped on biscuits or cornbread, spooned over pancakes or waffles, stirred into yogurt or oatmeal, or drizzled over ice cream.
The jam is also a great gift to share with friends, neighbors and family at the holidays. I love to pull a jar out of the pantry, tie a nice ribbon around the lid, and gift it to someone in December. I don’t have to fuss with baking or shopping during the busy season, and it’s nice to enjoy a taste of summer during the cold, gray months.
Preparation and Storage Tips
- Leave about ¼-inch of headspace in each jar. The proper amount of headspace in a jar is important to ensure a vacuum seal. If there’s too little headspace, the jam may expand and bubble out when air is being forced out from under the lid during processing.
- The jam will not set immediately, so it’s important to allow the jars to rest without interruption at room temperature until cool (or overnight).
- How to Store Blueberry Jam: Once the jam has had a chance to cool, check the seals. The lids should be down in the center or stay down when pressed. Unsealed jars should be refrigerated and used within 3 weeks. Properly sealed and processed jars of blueberry jam should be stored in a cool, dark, dry place (such as a pantry). The homemade blueberry jam will last for up to 1 year.
- Can you freeze blueberry jam? I do not recommend freezing this homemade jam. If you want to prepare blueberry freezer jam, you need to follow a recipe that is specifically designed for the freezer jam method.
How to Thicken Blueberry Jam
Most recipes for blueberry jam call for 2 boxes (or 3.5 ounces) of powdered fruit pectin. Over our many jam-making years, my mom has taught me to always err on the side of more pectin than recommended to ensure that the jam actually thickens. There’s just nothing more disappointing than runny blueberry jam!
That’s why I weigh out 4 ounces of powdered fruit pectin for each batch, which is equivalent to about ¾ cup of pectin (or slightly more than two boxes). I buy the pectin in bulk at a local country market, and then I don’t have to worry about partially-used boxes. Using a full 4 ounces of pectin results in a perfectly thick blueberry jam every time. Mom always knows best…
Why is my blueberry jam runny?
If your jam didn’t set, this could be the result of a number of different issues. Let’s troubleshoot!
- It can take 24-48 hours for a batch of jam to finish setting up. This thought goes through my mind every summer when I’m filling the jars and the jam looks thinner than I’d expect! I have to remind myself that it will not be thin once it cools and sets — patience is key.
- Overcooked Pectin: It’s important to boil the jam with the sugar for exactly 1 minute. If you overcook the pectin, it may break down and fail to gel.
- Reduced Sugar: I know that 8 cups sounds like a lot of sugar, but trust me: you need all of it! Stick with regular granulated sugar (instead of sugar substitutes like Splenda or stevia) and do not decrease the quantity called for in the recipe. Jam making is an exact science, so measuring the correct quantities of fruit, sugar and pectin are essential to a successful batch of jam.
- Doubled or Halved the Recipe: Since jam-making is an exact science (as noted above), many experts suggest that you should not try to double the recipe to make a larger batch or cut the ingredients in half to make a smaller batch. If you adjust the recipe in any way, the jam may not set properly.
If all else fails and your jam doesn’t set, don’t stress! Just re-name is “blueberry sauce,” and serve it with yogurt, ice cream, oatmeal, pancakes and waffles. It will still be delicious!
Why Add Lemon Juice to Jam
You won’t actually taste the lemon in the jam. Instead, the lemon juice serves a very specific purpose. The lemon juice lowers the pH of the jam, which neutralizes negative charges on the strands of pectin and helps your jam set. Again, no runny jam!
Why Add Butter to Jam
The butter is the only ingredient that is optional in this recipe (although I highly recommend including it). You can’t taste the butter in the final product; however, the butter serves a specific purpose. As you heat the berries, the proteins open up into strands that get tangled up and help stabilize the bubbles into a foam. Adding the butter (a fat) helps to prevent this tangling, and therefore reduces the amount of foam on top of your jam.
Do blueberries need pectin?
Pectin is a natural fiber found in plant cell walls, and most concentrated in the skin of fruits. It is water-soluble and binds with sugar and fruit acid to form a gel. The pectin is a necessary ingredient in this recipe, as it helps the jam set properly. The pectin also shortens the cooking time, resulting in a fresher blueberry flavor.
Is blueberry jam good for you?
As you can see from the list of ingredients, there is a lot of sugar in any jam recipe and therefore this treat should be enjoyed in moderation. Blueberry jam is a deep purple color, thanks to all of the antioxidants, vitamins, and flavonoids in blueberries! While it may be healthier to eat the blueberries on their own, at least you know you’re getting some additional benefits when you slather that beautiful homemade jam on top of your morning toast!
Can I use frozen blueberries to make this jam?
Use fresh, ripe blueberries for this recipe (not dried blueberries or frozen blueberries). Fresh berries have the best acidity and tannins to give the jam a more complex flavor, and the skins are the proper texture. Frozen blueberries tend to be mushier and more watery than fresh fruit when thawed, which will likely alter the consistency of your jam.
More Blueberry Recipes to Try
There are so many delicious ways to enjoy fresh blueberries at home!
- Blueberry Corn Muffins
- Easy Blueberry Cobbler
- Whole Wheat Banana Blueberry Muffins
- Blueberry Jam
- Old-Fashioned Blueberry Buckle
- Blueberry Streusel Muffins
- Easy Blueberry Muffins
- Blueberry Scones
- Peach Blueberry Cobbler
- Blueberry Cheesecake Bars
- Banana Blueberry Smoothie
- Blueberry Bread
Blueberry Jam
Ingredients
- 4 cups crushed blueberries (8 cups of whole fresh blueberries before crushing)
- 2 tablespoons freshly-squeezed lemon juice
- 1 teaspoon butter
- 4 ounces (about ¾ cup) powdered fruit pectin
- 8 cups granulated sugar
Instructions
- Prepare home canning jars and lids according to manufacturer’s instructions for sterilized jars. Keep jars hot until filled. Always use new lids.
- Place berries, lemon juice, butter and pectin in a large pot. Bring mixture to full rolling boil, stirring constantly. Stir in sugar. Return to a full rolling boil and boil exactly 1 min., stirring constantly.
- Remove from heat and skim off foam. Quickly ladle into the hot jars, leaving ¼-inch of head space at the top. Use a damp cloth to wipe any drips from the top and sides of the jars. Cover with hot lids and tighten rings firmly.
- Set the hot jars on a rack in a canner or in a large pot of boiling water. The water needs to cover the jars by at least 1-2 inches. Boil the jars for 10 minutes.
- Remove the jars from the boiling water and set on a towel or rack to cool overnight (but not more than 24 hours).
- When cool, check the seals. The lids should be down in the center or stay down when pressed. Store in a cool, dark, dry place. Unsealed jars should be refrigerated and used within 3 weeks.
Notes
- Make sure that you leave about ¼-inch of headspace in each jar. Leaving the proper amount of headspace in a jar is important to ensure a vacuum seal. If there’s too little headspace, the jam may expand and bubble out when air is being forced out from under the lid during processing.
- The jam will not set immediately, so it’s important to allow the jars to rest without interruption at room temperature until cool (or overnight).
- How to Store Blueberry Jam: Once the jam has had a chance to cool, you can check the seals. The lids should be down in the center or stay down when pressed. Unsealed jars should be refrigerated and used within 3 weeks. Properly sealed and processed jars of blueberry jam should be stored in a cool, dark, dry place (such as a pantry). The homemade blueberry jam will last for up to 1 year.
- Can you freeze blueberry jam? I do not recommend freezing this homemade jam. If you want to prepare blueberry freezer jam, you need to follow a recipe that is specifically designed for the freezer jam method.
Nutrition
This recipe was originally published in June, 2020. The photos were updated in June, 2022.
Can you cut this recipe in half?
Hi! Jam-making “experts” will tell you not to cut recipes in half, double recipes, etc. because in may impact the chemical process that helps the jam set up. That said, I’ve cut it in half before and didn’t have any issues. So, I say try it at your own risk. 🙂
I’m confused! 8 cups of fresh berries crushed is more than 4 cups crushed. Did you reverse those numbers! 8 cups sugar for 4 cups crushed berries seems a lot.
Should it be 4 cups fresh berries to become 8 cups crushed?
Hi Beverley! The numbers are correct. You’ll want to mash down 8 cups of large, fresh blueberries to get 4 cups (or close to it) of crushed blueberries.
Why so much sugar? Other recipes I’ve seen use around half that much.
Hi, Betty! That’s just the ratio of sugar to pectin to fruit that I’ve found to work well. I haven’t experimented with reducing the sugar because that has a tendency to change the consistency of the jam (and it often won’t set). That said, you can feel free to play around with the quantities and see if it works well for you with less of the sugar. Let me know if you give it a try!
I agree with you, 8 cups of sugar? That’s one cup of sugar to one cup of fruit! I made this recipe and only used 2 cups of sugar and it worked out great. It didn’t set to a full gel, but it wasn’t runny at all
Can you substitute powder pectin for liquid pectin? If so, what is the ratio between them? Thanks!
Hi, Chuck! No, those are not equal substitutes. You should be able to use liquid pectin instead of powdered pectin here, but it will require some modifications. I haven’t actually tested it myself, so I would refer you to this article, which is quite helpful: https://www.gettystewart.com/substitute-for-liquid-pectin/
Hope that helps!
Can you substitute powdered pectin for liquid pectin? If so, what is the ratio between them? Thanks!
Hey Blaine! I was just reading over your recipe again as I prepare to make my first ever batch of jam in the morning. I just noticed that they switched my grocery order to liquid pectin from powder when doing a pick up. Should I scrap the jam making and go get powder pectin?
Actually I googled it lol. May not be worth the risk.
Hi, Ranae! I haven’t tried this recipe with liquid pectin. It sounds like you already found your answer, but the two are definitely not interchangeable. It’s possible to use the liquid pectin, but you’ll need to make some adjustments. Here is an article that I would refer to if you want to attempt the jam with liquid pectin: https://foodinjars.com/blog/canning-101-how-to-substitute-pectin/
Hope that helps!
Thank you for responding! I didn’t see the other question that had already been posted in regards to this until after I posted! I’m heading to the store shortly! A rainy humid day is a good day to be inside making jam!
Absolutely! Enjoy, Ranae! 🙂
Hi Blair – this was my very first attempt at canning and I just knew that your Blueberry Jam was going to be a winner – and I was so right! Oh my goodness! I followed your (helpful and precise) recipe directions to the ‘t’ and everything came our perfectly! The prettiest color, texture, and just right sweetness (yes I was skeptical about those 8 cups of sugar but you were right!) I am so excited to see all my small jam jars lined up so beautifully! Thank you so very much! I’ll be making many more batches!
That’s wonderful to hear, Wendy! Welcome to the world of canning. 🙂 It’s so satisfying, and I’m glad that it was a success for you!
Ohhhh my goodness! This recipe is such a delight! We went blueberry picking and I had your recipe in mind. Ended up picking 18 pounds of fresh blueberries! Came home and got to work. It’s so therapeutic to can, isn’t it? It brings me so much joy. Anyways, my 3-year-old absolutely LOVES this so much that he requested to eat it by itself in a bowl! LOL! Everyone in my family loves it! I’m picking up some more jars so that I can make another batch this weekend. LOL! So good! Thank you so much for a wonderful recipe!
Wow, that’s a lot of blueberries! So glad that the jam was a hit. Yes, my kids could eat it with a spoon, too. 🙂 Thanks for your note, Shelly!
I used the feature on the recipe to increase the amount of servings; did a batch last night, now realized that your site doesn’t adjust the amount of blueberries as you increase the servings so now we have 1/2 as many blueberries in the batch as there should be. Now what do I do???
I have a question. I just recently started to make preserves. I have a glass top stove and read that I can’t use a regular canner. So I’ve been processing in my stock pot. Do you need to have a rack on the bottom for the water bath? I bought a silicone ring but it doesn’t cover the whole bottom of the pot and I can’t get all the jars in. Also, can you water bath half the jars at a time? Thank you!!
Hi, Rita! I don’t think you need a rack in the stock pot. I have canned jam in a stock pot without a rack many times, and it always works well. And yes — you can put the jars in the water bath in batches when you don’t have enough room to do them all at once.
When I made this recipe it turned out just like you said it would. I have had problems with other recipes and now yours is the only one I have kept.
Thank you so much, Keith!
Somewhat new to canning. Question about step 3. You say “Quickly ladle into the hot jars”. How do we keep the jars hot if they have already been sterilized?
Hi Kim,
Follow the instructions, and remove the jars from the hot water just before adding the jam. As long as you work quickly, they should stay warm enough! Here is a resource that might be helpful as well. Hope this helps.
Hi Blaire: Can I use 3/4 cup of Ball real fruit classic pectin?
Hi Marlene,
Yes, that should work just fine!