Introduction

Remember those summers at Grandma’s house? The smell of sun-ripened fruit bubbling gently on the stove? That’s the feeling I get every time I make homemade jam. And this Raspberry Rhubarb Jam? Oh, it’s pure sunshine in a jar! It combines the bright, sweet pop of raspberries with the delightful tangy bite of rhubarb, creating a flavor that’s absolutely unforgettable. And the best part? Using a low-sugar pectin means you get all that incredible fruit flavor without being overwhelmingly sweet. It’s surprisingly easy to whip up a batch, even if you’ve never made jam before. Trust me, once you taste this, you’ll be spreading it on everything!

Why You’ll Love This Recipe

Fast: Ready to jar up before you know it!
Easy: Simple steps perfect for beginners or experienced canners.
Giftable: Who wouldn’t love a jar of homemade goodness?
Crowd-pleasing: The perfect balance of sweet and tart that everyone adores.

Ingredients

Gathering your ingredients is half the fun! Here’s what you’ll need for this beautiful jam:

4 cups Raspberries: Fresh or frozen work wonderfully here. If using frozen, let them thaw first! These little gems bring sweetness and that lovely pink hue.
4 cups Cut/Diced Rhubarb: Give your rhubarb stalks a good wash and chop them into small pieces, about ½-inch chunks. No need to peel unless the stalks are super tough. This is where the wonderful tang comes from!
1 box Low sugar Sure Jell Fruit Pectin or No sugar needed Sure Jell Pectin: Make sure you grab the “low sugar” or “no sugar needed” box. These pectin types are specifically designed to set properly with less sugar, letting the fruit flavor shine.
2 Tablespoons Lemon Juice: Use fresh or bottled – either is fine! This little bit of acid is crucial for the pectin to set properly and brightens the flavor. Don’t skip it!
4½ cups Sugar: Yes, even low-sugar pectin recipes use some sugar! This amount provides sweetness and helps with the set and preservation.
1 tsp Butter (optional – used for canning): A tiny pat of butter added just before filling jars helps reduce foam on the surface of your jam. Purely aesthetic, but helpful if you want pretty jars!

How to Make It

Alright, let’s turn these simple ingredients into liquid gold! Follow along, and you’ll have glorious jam in no time.

Prep Your Fruit: Wash and chop your rhubarb as directed. Combine the chopped rhubarb and raspberries (thawed if frozen) in a very large, heavy-bottomed pot or Dutch oven.
Add the Pectin and Lemon Juice: In a small bowl, mix the pectin powder with about ¼ cup of the measured sugar (from your 4½ cups total). This helps distribute the pectin evenly. Add this pectin-sugar mixture and the lemon juice to the pot with the fruit.
Cook the Fruit: Place the pot over high heat and bring the mixture to a full, rolling boil that cannot be stirred down. Stir constantly to prevent sticking.
Add Remaining Sugar: Once you’ve reached that hard boil, stir in the remaining 4¼ cups of sugar gradually. Keep stirring as it dissolves.
Boil Again: Bring the mixture back to a full, rolling boil that cannot be stirred down. Start timing NOW and boil hard for exactly 1 minute, stirring constantly. This minute of intense boiling is crucial for setting the jam.
Remove from Heat and Skim: Take the pot off the heat. If using, stir in the teaspoon of butter now. Carefully skim off any foam that has risen to the surface using a metal spoon. This makes for a clearer, prettier jam.
Fill Jars (If Canning): If you’re canning your jam for shelf stability, ladle the hot jam immediately into hot, sterilized jars, leaving about ¼ inch of headspace at the top. Wipe the rims clean with a damp cloth, center lids on jars, and screw on bands fingertip tight.
Process Jars (If Canning): Place filled jars in a boiling water canner, ensuring they are covered by at least 1 inch of water. Bring the water back to a full boil and process for the time recommended for your altitude (check the pectin box instructions for specific times).
Cool and Check Seals: Carefully remove jars from the canner and place them on a towel on the counter to cool completely (this can take 12-24 hours). You’ll hear the satisfying “pop” as the lids seal. Check seals by pressing the center of the lid – it should be concave and not spring back.
For Refrigerator/Freezer Jam: If not canning, let the jam cool slightly in the pot, then ladle into clean jars or freezer-safe containers, leaving headspace for expansion if freezing.

Substitutions & Additions

Want to play around a bit? Jam making is forgiving and fun! Here are a few ideas:

Different Berries: Not a raspberry fan? Try strawberries, blueberries, or a mix! Adjust the total fruit amount to 8 cups.
Add Some Zest: A teaspoon of orange or lemon zest added with the lemon juice can brighten the flavor even more.
Spice It Up: A pinch of ground ginger or a scraped vanilla bean pod added during cooking can add a lovely warmth.
Use Different Pectin: You could use regular pectin, but you’d need a lot more sugar (usually 7 cups) and the process for adding sugar is different. Stick to low-sugar pectin for this recipe as written!

Tips for Success

Making jam is pretty straightforward, but a few little tricks can make all the difference:

Use Ripe, But Not Overripe Fruit: Fruit that’s just ripe has the best flavor and pectin content (even though we’re adding pectin, quality fruit helps!).
Don’t Skimp on Lemon Juice: It’s essential for the pectin to activate and set the jam properly.
Measure Accurately: Especially the sugar and pectin. Jam making is a bit of science!
Use a BIG Pot: The jam boils vigorously, and you don’t want it boiling over and making a huge mess. Use a pot much larger than the volume of your ingredients.
Boil Hard: That “full, rolling boil that cannot be stirred down” is key for activating the pectin with the sugar. Don’t let it just simmer.
Prepare Ahead: If you’re canning, have your jars, lids, and canner ready to go before you start cooking the jam, as you need to fill them immediately.

How to Store It

Once your beautiful jam is made, here’s how to keep it delicious:

Canned Jam: Properly canned and sealed jars can be stored in a cool, dark place (like a pantry) for up to 1 year. Once opened, refrigerate and use within a few weeks.
Refrigerator Jam: Store in clean jars or containers in the refrigerator for up to 3 weeks.
Freezer Jam: Pour into freezer-safe containers (leaving headspace!), cool completely, and freeze for up to 6 months. Thaw in the refrigerator.

FAQs

Got questions? I’ve got answers!

Q: Why do I need lemon juice?
A: Lemon juice adds acidity, which is necessary for the pectin to work correctly and create a firm set in your jam.

Q: What’s the butter for?
A: A tiny bit of butter helps reduce foam when the jam boils. It doesn’t affect the flavor or set, just makes for clearer-looking jam in the jars.

Q: Can I use frozen rhubarb?
A: Yes, absolutely! Just thaw it completely before measuring and adding to the pot.

Q: My jam didn’t set! What happened?
A: Common reasons are not using enough lemon juice, not measuring ingredients accurately, or not boiling hard for the full time after adding the sugar. Sometimes it just takes longer to set as it cools. Give it a full 24-48 hours before assuming it’s a failure. If it’s still too runny, you can try to remake it following pectin package directions for runny jam.

Sweet & Tangy Homemade Raspberry Rhubarb Jam (Low Sugar Option!)

This recipe combines the bright, sweet pop of raspberries with the delightful tangy bite of rhubarb to create a flavorful jam. Using a low-sugar pectin allows the fruit flavor to shine without being overwhelmingly sweet. It's surprisingly easy to whip up, perfect for beginners.

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Equipment

very large, heavy-bottomed pot or Dutch oven
Small bowl
metal spoon
Jar(s) clean or sterilized, for filling
boiling water canner optional, if canning
lids optional, if canning
bands optional, if canning
damp cloth optional, if canning
towel optional, for cooling jars

Ingredients

Main Ingredients

4 cups Raspberries Fresh or frozen (thawed if frozen)
4 cups Cut/Diced Rhubarb Chopped into about ½-inch chunks
1 box Low sugar Sure Jell Fruit Pectin or No sugar needed Sure Jell Pectin
2 Tablespoons Lemon Juice Fresh or bottled
4.5 cups Sugar
1 tsp Butter optional - used for canning, helps reduce foam

Instructions

Prep Your Fruit: Wash and chop your rhubarb as directed. Combine the chopped rhubarb and raspberries (thawed if frozen) in a very large, heavy-bottomed pot or Dutch oven.
Add the Pectin and Lemon Juice: In a small bowl, mix the pectin powder with about ¼ cup of the measured sugar (from your 4½ cups total). Add this pectin-sugar mixture and the lemon juice to the pot with the fruit.
Cook the Fruit: Place the pot over high heat and bring the mixture to a full, rolling boil that cannot be stirred down. Stir constantly to prevent sticking.
Add Remaining Sugar: Once you've reached that hard boil, stir in the remaining 4¼ cups of sugar gradually. Keep stirring as it dissolves.
Boil Again: Bring the mixture back to a full, rolling boil that cannot be stirred down. Start timing NOW and boil hard for exactly 1 minute, stirring constantly. This minute of intense boiling is crucial for setting the jam.
Remove from Heat and Skim: Take the pot off the heat. If using, stir in the teaspoon of butter now. Carefully skim off any foam that has risen to the surface using a metal spoon.
Fill Jars (If Canning): If you're canning your jam for shelf stability, ladle the hot jam immediately into hot, sterilized jars, leaving about ¼ inch of headspace at the top. Wipe the rims clean with a damp cloth, center lids on jars, and screw on bands fingertip tight.
Process Jars (If Canning): Place filled jars in a boiling water canner, ensuring they are covered by at least 1 inch of water. Bring the water back to a full boil and process for the time recommended for your altitude (check the pectin box instructions for specific times).
Cool and Check Seals: Carefully remove jars from the canner and place them on a towel on the counter to cool completely (this can take 12-24 hours). You'll hear the satisfying "pop" as the lids seal. Check seals by pressing the center of the lid – it should be concave and not spring back.
For Refrigerator/Freezer Jam: If not canning, let the jam cool slightly in the pot, then ladle into clean jars or freezer-safe containers, leaving headspace for expansion if freezing.

Notes

Tips for Success:
- Use Ripe, But Not Overripe Fruit.
- Don't Skimp on Lemon Juice: Essential for pectin to activate and set.
- Measure Accurately: Especially sugar and pectin.
- Use a BIG Pot: Prevents boiling over.
- Boil Hard: The 'full, rolling boil' is key.
- Prepare Ahead: Have canning supplies ready if canning.

Storage:
- Canned Jam: Store in a cool, dark place for up to 1 year. Refrigerate after opening (use within a few weeks).
- Refrigerator Jam: Store in the refrigerator for up to 3 weeks.
- Freezer Jam: Pour into freezer-safe containers (leave headspace), cool, and freeze for up to 6 months. Thaw in the refrigerator.