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Green Plum Jam is an excellent way to use unripe plums. You might have an excess of green plums due to pruning your plum tree or because of a surprise windfall. This 2 ingredient jam is a perfect solution, it’s delicious, quick and easy and needs no jam sugar or added pectin.
When we moved into our new house at the end of last year we were so excited to discover a plum tree in the back garden.
I like to think I know a fair amount about food and produce but it turns out I know nothing about how to care for a fruit tree. So it completely caught me by surprise one morning to discover our plum tree had completely broken in half overnight. Hundreds of green plums had scattered all over the grass and many were still clinging in last desperate hopes to the fallen branches.
We had no idea that this situation is inevitable if you don’t prune your green plums regularly from your plum tree. The weight of the growing fruit is often too much for its spindly branches. So if you have a plum tree in your back garden it’s more than likely at some point you will have a load of green plums which you won’t know what to do with.
Can you eat green plums?
Yes you absolutely can. They are quite hard though and very sour so you wouldn’t eat it from the fruit bowl like you would a ripe plum. However they are excellent to cook or bake with.
Can you use unripe plums for jam?
They are ideal for jam as they bring all the lovely tart plum flavour. The finished jam is also not too sweet as the fruit itself has lots of flavour
What else can I do with unripe green plums?
You can use green plums in any recipe that you might a ripe plum, although you might need to add a little extra sugar.
Try this Plum and Beetroot Chutney – I made it with unripe green plums!
Why is Green Plum Jam such a brilliant recipe?
- Just 2 ingredients – plums and sugar. The plums are so flavourful they need nothing else.
- Plums are an excellent source of pectin too so you don’t need to add any extra or use special jam sugar.
- It’s quick and because plums have their own special pectin you don’t need to boil for ages to achieve set – 5-10 minutes is enough.
- It’s not too sweet because the plums are unripe and don’t bring an excess of sweetness to the jam.
- The flavour is sharp but very plummy and can be used with so many sweet or savoury dishes, besides being delicious on a crumpet.
How do you make plum jam?
- Place the plums in a large preserving pan or saucepan and heat until the plums have completely broken down into a pulp.
- Remove the plum stones which will be floating within the pulp.
- Pour the sugar into the pan with the plums and bring up to a rolling boil, stirring occasionally.
- Boil hard for 5 minutes and test for set using the wrinkle test. If it’s not quite there then boil for a further 2 minutes.
- Once the jam has reached setting point then decant into sterilised jars.
Le Creuset Large Casserole Dish – my favourite preserving pan. Everything cooks evenly, it’s incredibly resilient even if you accidently burn your chutney a little to the bottom (remember to stir!!) and we use it for everything.
Do you need to peel the plums?
No, the unripe skins are quite fine and dissolve deliciously into the jam.
Do you leave the stones in?
Leave the stones in the jam whilst you are simmering the whole plums. When the plums had broken down into a pulp then remove the stones before you add the sugar. You can do this manually but it might be a bit hot. A slotted spoon should do the job. Check for any errant stones when the jam is finished and as you are putting into jars. They are quite easy to spot at this point.
How do you know if your jam has reached setting point?
Jam has reached setting point when it’s 105°C/220F. However this is not my preferred test. I find the ‘wrinkle test’ gives a very accurate indication if jam is ready to be put in its pots.
What is the ‘wrinkle test?’
The wrinkle test is when you quickly cool a teaspoon of the jam and push the jam with your finger. If it wrinkles up then it’s reached the right setting point.
- Place a few saucers in the freezer before you start making your jam.
- When you think your jam should be ready, it’s been boiling hard for at least 5 minutes, the sugar has completely dissolved and the jam is feeling a little heavier when you stir it, then you are ready for the test.
- Turn the heat off the jam. Remove a saucer from the freezer and drop a small teaspoon of jam onto the saucer.
- The jam should not be too runny. Place the saucer into the fridge for about 30 seconds.
- Remove the saucer from the fridge, at this point the jam should have set. Push the jam with your finger, if the jam wrinkles up then it’s ready.
- If it doesn’t then turn the heat back on and boil your jam for a further 2 minutes before you test again.
How do I fix runny plum jam?
It’s happened to us all, you have bottled your jam and found that once it has cooled then the set is a little too runny. Don’t worry you can simply pour the jam back out of their jars and re-boil it until it reaches a better set.
You must wash and re-sterilise your jars and lids though before you decant the jam back into the jars.
How long does the jam keep for?
Unopened the jam will last for up to a year if stored in a cool dark place. Once opened keep in the fridge and the jam should last a month.
Can you make this jam with ripe plums?
Absolutely, it will be just as delicious but a little sweeter. You could also use greengages.
Can you reduce the sugar?
Yes you can but the sugar doesn’t only provide the sweetness it also stops the jam from spoiling. If you reduce the sugar it won’t keep as long unopened.
Can you use frozen plums to make plum jam?
Yes. You don’t need to defrost the plums before beginning the recipe, they will just slightly longer to break down initially since they are frozen.
What can you eat with plum jam?
Jam is excellent on buttered toast or crumpets of course but it’s not the only use.
- As a filling in a Victoria Sponge.
- Spread thinly in a cheese sandwich.
- On a cheese or charcuterie board.
- Sticky sausages - Mix 2 tablespoons of jam and 1 tablespoon Dijon mustard and use it to smother over cocktail sausages before baking in the oven for 20 minutes.
- Sweet Cheese Quiche. It’s still a savoury quiche but the taste is fantastic - mix in a couple of tablespoons of green plum jam into the filling of this Homemade Quiche. You will forever make your cheese quiche this way.
- Jam tarts - see this amazing gluten free pastry recipe!
If you love homemade jam then have a look at these recipes:
Green Plum Jam
- 1500 g green plums
- 1250 g granulated sugar
- Place the plums in a large preserving pan with 100ml water. Turn onto a gentle heat and cook the plums until they have broken down into a thick pulp.
- Remove the plum stones manually which should be floating within the pulp.
- Pour the granulated sugar into the pan with the pulp.
- Heat the pan and bring to a rolling boil, making sure to stir the bottom of the pan frequently so the fruit doesn’t stick.
- Boil the jam hard for 5 minutes, whereupon it should have reached setting point.
- Turn the heat off the jam and check for setting point with the wrinkle test.* If it doesn’t wrinkle then turn the heat back on and boil again for 2 more minutes before testing again.
- Once the jam has reached setting point then decant into sterilised jars*.