whole food ~ well made

Expert rhubarb jam at

How to Make Rhubarb Jam Like a Pro with a Q&A

It’s late at night, but I am nonetheless babysitting a giant black pot of simmering water. Within it are jars filled with rhubarb jam, fresh from the field behind my house.

This is what we home canners, we preservers, we local food lovers do. Against the wishes of our spouses, our bodies, ourselves.

We do it because it is good and necessary. It brings its own rewards far better than the other tasks pressing upon us.

On this night, I know that I should be writing at least one article, tracking expenses, or at the very least, sleeping.

But what can compare with a dozen pint jars of a garnet-colored preserve that I can spread on toast for my daughters, give as casual “thank you” gifts and stack on my shelves in a way that feels like gold bars?

This canning is more of an accomplishment than anything else I’ve done sitting at my desk during the past month.

Expert rhubarb jam at

Ah yes, rhubarb. I love it dearly, and it reminds me that from here on out until October, I will be spending many a late night–while my daughters sleep and others relax and play–standing by a stove.

Waiting–tired and fulfilled. Care to join me?

Expert Jam Session

Recently, I spent an afternoon with my friend and award-winning jam maker, Rebecca Staffel. A former cookbook editor at Amazon, literary agent and Microsoft executive, Rebecca turned her penchant for preserves into Deluxe Foods in 2010. {It has since closed.}

She sources all her fruit from local farms and uses old-world techniques to boil them into singular jams, chutneys, jellies and conserves, —all in a tiny commercial kitchen in Seattle.  Full of humor and generous tips, Staffel describes herself as “jam passionate.”

Expert rhubarb jam at

Here are some of her top jam making tips:

Here are some of her top pro tips:

  • let the fresh fruit and sugar spend time together to macerate the fruit so you don’t have to cook it as long
  • pectin is a natural product (read: not evil) that is commercially made from citrus
  • a looser set is preferably to a gummy texture with the finished jam
  • the USDA required hot water canning, but you literally cannot kill anyone with a jar of jam

Pectin, Canning Methods and Other Jam FAQs

Q: A lot of people are trying canning for the first time, so I want to ask you about the thickening process where fruit becomes jam.
RS: It starts with the fruit, because depending on what fruit you pick that’s going to have its own pectin content. Less ripe fruit has more pectin but less flavor. Riper fruit has more flavor, less pectin. Personally, I don’t mind it dolloping. My bias is for peak-of-the-season fruit, which might make for a slighter looser preserve but it’s going to have maximum flavor.

Q: What about pectin you buy in a package?
RS: I don’t use commercial pectin. We just rely on the pectins in the fruit with lemon juice and sugar. We do a lot of work with maceration. So, we let it [fruit and sugar] sit overnight. The sugar pulls the water out of the fruit, and basically starts candying the fruit while it sits there overnight. That lets us cook the preserve for a shorter period, which I like.

Q: What is commercial pectin and why don’t’ you use it?
RS: Commercial pectin is completely natural. It’s not evil. Pectin is fruit based, generally citrus. I don’t use it because I don’t care for the gummy texture.

Q: I’m like you, a like a looser jam, but my daughters don’t’ like it dripping out of their peanut butter and jelly sandwiches. What do you do to test your set?
RS: I cook to temperature, to 220 °F, with a couple of exceptions. Apple butter, pear butter, we cook until a spatula stands up in it—so that’s kind of fun. Plum, it’s hard to get Italian prune plums past 218°F. It’s hard to get apricots to go past 218°F without overcooking them, so I just give in and have a soft set with apricot, but with plum you’ll get a firm set.

Expert rhubarb jam at

Q: When I first starting canning jam it was blackberry—a good beginner jam—and the woman I was canning with filled the jars, put on the lids and turned them upside down. Other cookbooks do the oven method, while the USDA only approves of the boiling water canning method. What’s the deal?
RS: There is no way you can kill someone with a jar of jam unless you throw it at their head. The botulinum spores do not grow in the high-sugar and high-acid environment of the jam. There are no invisible killers in jam. If you get white or blue fuzz, do not eat that jam. If it’s in the fridge and it starts to crystallize, it’s bad quality. Life is short, don’t eat bad quality jam.

Q: What’s the difference between the rolling water boil method and the oven method?
RS: The rolling water boil method is the USDA-approved method for home canning. You can do oven canning in a commercial kitchen that’s inspected [by the government]. At Deluxe Foods we do oven canning. My feeling is that while my oven may be different than your oven, there are no two ways about boiling water. It is always 212 °F. Maybe we mess with elevation, but there is not a 50-degree swing in the rolling water boil. Also, when you start to branch out to pickles or canning fruit, you’re going to have to do the rolling water boil, so you might as well learn how to do it.

Q: Do you have a jam jar you prefer?
RS: Funny you should ask. I have been evolving in my jar choice. I used to use the regular mouth and I liked those crystal jars just because they’re pretty. Recently, I have switched to wide mouth. I prefer the half pint. Twelve ounces is too much jam.

I have to say two more things about jars. When you have finished jarring up your jam, let it sit for 24 hours. Don’t touch it, don’t move it because that is the time when your set is happening. Once the 24 hours is over, and you’re bored of jam and you can’t believe you even started on this project, you just throw it in the cupboard and forget about it. Don’t do that! Always take the time, to label what it is, the date, and, as a bonus, who made it.

Q: Do you have any reflections on the pure labor of love jam making entails?
RS: I urge people to make small batch because it’s the right amount of labor. You get out of the jam what you put into it. So if you were feeling attentive and loving on the fruit, that’s going to come through in the jam. Not so much that it fills you with wrath because you’re sick of looking at rhubarb.

Expert rhubarb jam at  For detailed jam making instructions, head on over to this post all about marmalade {that also applies to jam}.


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Expert rhubarb jam at
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5 from 1 vote

Rhubarb Double Ginger Jam

The British sure know their jam, so I use this recipe I adapted from the BBC Good Food Magazine that I've infused with Rebecca's jam-making advice. It calls for fresh ginger and crystallized ginger.
Course Preserves
Cuisine British
Prep Time 15 minutes
Cook Time 20 minutes
Total Time 35 minutes
Servings 4 pints
Author Lynne


  • 2 1/4 pounds rhubarb, chopped into 1/2-inch sections about 10 cups
  • 5 cups granulated sugar
  • 1 2-inch piece fresh ginger, peeled and very finely minced or grated
  • 1/4 cup finely chopped crystallized ginger
  • pinch sea salt
  • 1 packet liquid pectin


  • Combine the rhubarb, sugar, fresh ginger, crystallized ginger and salt in a large non-reactive pan. Stir well, cover and leave for 2-24 hours to allow the rhubarb to release its juices and jump start the jam process. If you have the opportunity, stir the mixture a few times.
  • Bring the mixture to a boil over medium-high heat, stirring frequently. Meanwhile, put a small plate in the freezer to use later to check the set. And sterilize pint or half pint jars if you plan to can the jam.
  • Let the rhubarb boil for 8-10 minutes, stirring and then add the pectin, according to the instructions on the package. Cook for 2-3 minutes then check it by putting a puddle of the hot jam onto the frozen plate. Let it set for moment and then check to see if it forms a glossy sheet that wrinkles when you push a finger into it. If it doesn't cook for 2-3 minutes more and test again.
  • Ladle into sterilized jars and let cool completely or process in a hot water bath for 10-minutes following these detailed instructions from the Center for Food Preservation.


  1. melona will

    5 stars
    This was my first attempt making any kind of jam. I am glad I chose this recipe. It is excellent. I didn’t have the crystallized ginger so just used more of the regular ginger. Next time I will try it with both ginger’s. The recipe is easy and the jam turned out exceptional. Thanks Lynne for the quick response to the few questions I had . I can’t wait to give some to friends 🙂

    1. Another jam maker in the world! So glad you had a good experience with this recipe, Melona. Thanks for sharing your comment–and your homemade jam.

  2. Julia

    HI! I know you say you can’t kill someone with jam, but I’m always worried about changing up a recipe that I intend to process to be shelf stable. Can I leave out the ginger without messing up the ph? I love just rhubarb jam and have a hard time finding it without it being strawberry-rhubarb, etc.

    Also, you note that you don’t use commercial pectin, but the recipe calls for it. Is it optional? Even for jam intended to be processed in a water bath?

    Thank you!

    1. LOL, Julia–and great question. Yes, you can definitely leave out the ginger. For general reference, if the ratio of fruit to sugar don’t change, you can mess around with the flavorings whenever you make jam. As for your question about pectin, the interview subject does not use it, but I do. And so it is included in this recipe to get a good set. Hope that clears things up!

    2. Julia

      Ah yes! Thank you! That’ll teach me to skim the intro 🙂 Thanks for the prompt reply!

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