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We’re on a canning spree this week. The air is crisp and the mornings are cool. We’re surrounded by a fiery array of leaves that rustle in the warm afternoon breeze. Fall is in the air and canning just feels right this time of year.
I could eat this plum jam by the spoonful; paired with a hot mug of tea (I’m totally day dreaming here)… Our tiny plum tree overproduces the most amazing little plums every year. I wish I could name this variety; anyone recognize these little beauties?
This recipe is really a cross between plum jam and plum preserves. It still has some of it’s preserve-like plum chunks, but it’s nice and thick and spreads beautifully. It’s awesome paired with breakfast pancakes or crepes. Oh and this would make the sweetest Christmas gift!
Home Canning Tools:
- 8 pint-sized jars with lids. I purchased them at Walmart.
- Large Stock Pot (20Qt+) with Rack (or purchase a canner)
- Jar lifter to safely transfer the jars
How to Make Plum Jam:
Cooking the Preserves:
1. Cut 12 lbs of plums in half, pit them and place in a large mixing bowl. Drizzle well with 4 1/2 cups sugar. Using a large spoon, stir plums with sugar until all are coated. If your plums are overripe or already very sweet, you may only need 4 cups of sugar total. You can add more sugar to taste while its cooking. Let plums sit at room temp with the sugar for about 1 hour, or until sugar is somewhat dissolved.
2. Transfer plums/sugar mixture in to a large cooking pot. Place it on the stove uncovered and bring to a boil, stirring occasionally. Make sure if you see a light boil to stir because the whole pot may not be boiling, just the center. If it stops boiling after you stir it, continue boiling until everything is uniformly bubbling, then simmer for 10 minutes and turn off the heat. Let the pot stand uncovered until it is just warm to the touch or reaches room temp.
3. As soon as it cools, repeat step 2 the same way – simmering 10 minutes. You will bring it to a simmer a total of 4 times, stirring to prevent scorching the bottom. This is why it takes 2 days to make. It’s really easy though and so worthwhile! There’s no “set” waiting time between boilings. If 2 days doesn’t work for you, by all means, take 3 days. Preserves have plenty of sugar so they won’t spoil at room temp if you leave it on the counter overnight. If you want the preserves to have an even thicker consistency, you can boil it 5-6 times if you wish.
(Note: the fourth time you boil, bring it to a boil over a little lower heat and stir a few extra times to prevent scorching. Also, it thickens more as it cools. If using a different type of plum, I suggest adding sugar to taste in case they are more tart)
4. The last time you bring it to a boil you will want to transfer it to sterilized jars while it’s boiling hot.
To sterilize the jars:
1. Start by washing your jars and lids with warm water and soap then let them dry in the oven at 215 for about 20 min or until completely dry. Boil the lids 5 min.
2. Transfer your boiling hot jam to the jars using a glass measuring cup and a funnel (least messy method) leaving about 1/2″ space.
3. Screw the lids on enough to keep a tight seal in place but don’t over-tighten them since air bubbles need to be able to escape.
Current Canning Guidelines:
Get up to date on the most recent canning guidelines here. It’s a great resource to answer frequently asked canning questions. Current guidelines recommend the following process (instead of oven canning):
- Place packed cans into the canning pot and cover with 1-2 inches of water. Bring to a boil and process 15 minutes.
- Remove from the pot and leave at room temperature undisturbed for 12-24 hours. You may hear a pop when the jars fully seal.
- After 24 hours, check that the seal has formed by pushing down on the center of the lid – it should not move at all. If the seal does not form, refrigerate jam and enjoy within 3 months.
Now don’t you want to curl up with a jar of that?
Plum Jam Recipe (No Peel, No Pectin!)
Ingredients
- 12 lbs sweet ripe plums, rinsed
- 4 1/2 cups white sugar
- 8 pint-sized jars with lids.
Instructions
- Place pitted and halved plums into the mixing bowl & drizzle with 4 1/2 cups of sugar. Stir plums until all coated with sugar. Let them sit for 1 hour then transfer the mixture into a large cooking pot.
- Bring it to a boil uncovered, stirring occasionally. Boil until the mixture is bubbling uniformly. Simmer for 10 minutes then turn off the heat. Cool to room temperature.
- Repeat step 2 a total of FOUR times. Last time bringing it to a boil at the lower temperature, stirring frequently to prevent scorching.
To Sterilize Your Jars:
- Start by washing your jars and lids with warm water and soap then let them dry in the oven at 215 for about 20 min or until completely dry. Boil the lids 5 min.
Filling and processing your jam:
- Transfer your boiling hot jam to the jars using a glass measuring cup and a funnel (least messy method) leaving about 1/2″ space.
- Screw the lids on enough to keep a tight seal in place but don't over-tighten them since air bubbles need to be able to escape.
- Place packed cans into the canning pot and cover with 1-2 inches of water. Bring to a boil and process 15 minutes. Remove from the pot and leave at room temperature undisturbed for 12-24 hours. You may hear a pop when the jars fully seal. After 24 hours, check that the seal has formed by pushing down on the center of the lid - it should not move at all. If the seal does not form, refrigerate jam and enjoy within 3 months.
Recipe updated in 2019 to reflect new canning standards. Previously we used the oven method: screw the lids on enough to keep a tight seal in place but don’t over-tighten them since air bubbles need to be able to escape and place in the oven at 350˚F for 15 min then carefully remove from oven, flip upside down and let cool to room temperature.
Signs of Spoiled Canned Food:
With any type of canning, we follow this advice: “When in doubt, throw it out”
Discard and do not eat or taste any canned food if you notice any of the following:
- the jar is leaking, bulging, or swollen
- the jar looks damaged, cracked, or abnormal
- the jar spurts foam or liquid upon opening
- the canned food is discolored, moldy, mushy, slimy, or smells bad
I hoping that since you’ve posted on this website this year you’ll see this despite how old this specific post is.. Can you tell me why the jam needs to be cooled fully between boils instead of just boiled down all at once? What does this do chemically?
I don’t know the science of it, but it does help the jam to thicken to let it cool down in between. It also helps the fruit not become mush and keep some of it’s form better. If you’re making jams with certain fruits like apricots, they can turn dark brown rather than that golden color if you boil them too long.
This is the first time I’ve ever canned. I followed your recipe exactly how it was written, at least I think)… Everything looked fine until I put the jars in the oven at 350, after 14 minutes jam had spilled out of jars. What do you think I did wrong? They were about a half inch from the top of jar, & all I can think of is they were in there too long or I screwed the top on too tight which I don’t think I did, or maybe I didn’t screw them on tight enough? Please help because this jam is delicious. I hope it’s not scorched due to oven.
Thanks,
Brandi
I haven’t had that experience but we’ll try to troubleshoot it :). Did you have them in the center of the oven? Not to high up in the oven?
I am using your recipe to make jam for the first time, is it supposed to get foamy when you boil? Thank you for sharing your recipe. It seems simple enough even a first timer can do it! 🙂
It does have a little bit of foam but not a crazy amount. Make sure you are simmering for 10 minutes after it comes to a boil and not boiling the entire time. I hope that’s helpful 🙂
Our flowering “fruitless” plum tree got a wild hair this year and is making plums for the first time in 20 years. They’re tart but have a good plum flavor. I’m going to try out this recipe, but question: what is the “No Peel” part? Do the peels dissolve after so much cooking? Thanks!!!
The peels meld into the jam really well and they aren’t bothersome at all. After they are cooked for so long, you can hardly tell they are there. I loved that they added to the texture of the jam so it’s not just mush. Congrats on your plum tree producing! I’d be totally excited about that too! 🙂
Makes a great jam. I was skeptical about not boiling off the skins, but it worked great. Borrowed neighbor’s fish scale to weigh plums, worked fine.
I’m so happy you liked the jam 🙂 Fish scale is better than no scale 😉 Whatever works!
Hi! Just wondering, why do the jars need to be turned upside down once they come out of the oven?
It helps them seal
I’m a self sufficiency tragic and love making plum jam but struggle with using a knife to cut the stones out as the plums are extremely juicy, which almost makes it a tedious, raincoat job.
I had a light bulb moment seeing a corer in your lead picture, it works brilliantly, little mess and much quicker than the knife method. Removing the stones as they rose after the first boiling while stirring was relatively easy, this was suggested in an ancient copy of Mrs Beeton’s.
The recipe has a delightful, slow cooking feel about it, good stuff Natasha.
I like the slow food style of the recipe
What a great tip!! I too despise those little pits. Thanks so much for sharing!! 🙂
I am so glad I found this lovely recipe for making plum jam. I’ve made plum jam the traditional way for many years but liked the idea of not using so much sugar. I always love home-made plum jam and the texture and colour using your recipe is superb. We have a heat-wave in NSW at present and the plums have ripened quickly. I’m about to have some on a slice of bread and butter.
I’m so glad you’re enjoying the recipe 🙂 and water weather. There is snow on the ground in Idaho! 🙂
I’m making this jam today. Do I let it “boil for 10 minutes” each of the following times that I boil it or just let it come to a boil then let it cool again?
Let it simmer for 10 mins each time and make sure to stir the mixture to avoid any scorching :). Hope this helps.
Thanks!
I was curious why you put the jars upside down? Do you store them this way also? Love this recipe.
It helps them seal properly. You can turn them right side up once they are at room temp.
Hi Natasha,
I am making jam for the first time, your recipie looks awesome. I am in the middle of making this:
I see a lot of skins shruken and floating around, I don’t know what to expect.
Also, I added some small pieces of pears.
And I may have eyeballed sugar, lesser than required, does that make a difference?
What should I do.
It should get thicker with every boil and the skins should be fine. I’m not sure how the pears will change things since I haven’t tried making pear jam. You’ll want to add sugar to taste but it should be fairly sweet in the end to keep it preserved.
Hello Natasha! I just wanted to thank you for this lovely jam recipe. I am here in Idaho as well, and we have a plum tree that is just LOADED, but ready to go due to the recent frosts. I have made plum butter & plum syrup in the past, but wanted something a little different this time. So I have your recipe cooking away in the crockpot right now.
This method also works for pears (except w/ pears, it’s better to peel them), & makes the most heavenly pear jam ever, especially if you add a couple of vanilla beans to soak the entire time you are cooking it down.
God bless you & your family ~
Carol
Hello my fellow Idahoan! 😉 That makes me wish we had a good pair crop this year. My parents pears and apples both did not do well this year. Thank you for sharing. It’s great to know that it works for pears as well.
Hi Natasha, I followed your canning process but wonder that the plum jars can be kept at room temperature or they still need to be in the refrigerator? Thanks!
Once they are sealed and have cooled down to room temperature, you can leave them at room temperature. No need to refrigerate, unless you open them. If they are open they do need to be refrigerated.
I feel compelled to add my 34 years of jam-making experience to the waterbath recommendations. I too heat the jars to 215 degrees in the oven, boil the lids for 5 minutes, after filling turn the jars upside down for 5 minutes and then turn them right side up, listening for the “ping” as the vacuum is formed. I have always used the least amount of sugar I can get by with. I have done this at altitudes of 7,800 feet and sea level and everything in between. I have kept these jars for over a year and have NEVER experienced any spoilage! Just be clean and be accurate with your times and temperatures and your end product will be fine.
My mom has used your method for as long as I can remember! She doesn’t boil her cans either. All this peer pressure is gettin’ to me! 🙂
I am wondering if this would work for apples. I just inheritated a pick of plums and a bushel of apples. i have done first canning of beans, and proudly display them in my open corner cabnets. plums will look great up there. thanks.
I haven’t tried it with apples so I can’t really recommend it, but what a great idea to display the canned goods. Thanks Michelle! I’ve been keeping mine in the laundry room. 🙂
Can I substitute honey for half of the sugar or will it not work for the consistency?
That should work fine. If you want it thicker, just simmer it a little longer, just be careful not to scorch the bottom toward the end.
It could have been a little thicker, but looks great, tastes great! Thanks for the great recipe! 🙂
Some plums are juicier than others. If you want it thicker, just boil it down one more time, but be very careful not to scorch to the bottom of the pot! (Speaking from experience) 😉
It didn’t let me rate it with my reply. Five star for sure!
Thank you so much 🙂
These plums are Mount Royal plums and do not need 2 trees to be pollenated. They are self-pollenating! 🙂
Thank you for sharing Debbie :), good to know.
Hey Natasha,
I made your peach preserves not long ago and I really regret having only made half of the recipe as I have finished almost all of it already. I’m going to try this recipe next. I was wondering if you have a good recipe for apple butter since its fall and the apples are so delicious. Thanks
Apple butter… mmmm. I don’t have one (yet). That sure sounds good! If you find an amazing recipe, do share! 🙂
Another success ! I added some chinnamon nutmeg and ground ginger and turn it into spiced plum preserves. Thanks for the great recipe and technique.
Awesome :), I’m glad you like the recipe.
Food poisoning isn’t worth it. Use a water bath canner. The upside down method is no longer endorsed by the FDA. Check with your extension agent. They can give you options, but heating your jars in the oven is not one of them.
I’m glad to find that info out (as you can see the links and such that I added above) I need to buy a water bath canner. Next time I’ll try that version. P.S. What is an extension agent?
You don’t need a special “canner”. Any large, heavy pot which is deep enough so that the water covers the jar tops.