In a good year, with favourable weather, a single plum tree will produce more fruit than one household can reasonably manage. Some years the branches of my plum tree become so laden with fruit that they hang down to the ground.
All types of plum – from cultivated varieties like Victoria to less common greengages and mirabelles – make excellent jam, thanks to their high pectin levels, which is the compound that makes jam set. The tarter the fruit, the higher the pectin level, so the firmer the set. This jam recipe includes a little lemon juice (also high in pectin) to ensure that even a very ripe, sweet plum harvest can be made into perfectly set fruit.
Even a small crop is worth turning into a few jars of jam. Jam making is, for me, a landmark moment in late-summer. I spend a lazy Sunday afternoon stoning the fruit and bubbling the jam, then labelling the jars and filling my cupboards for winter. It’s a wonderful way to mark the changing seasons and prepare for winter hibernation. Come December, when I open a jar, I am reminded of those fleeting, hazy summer days picking plums.
How to make plum jam
Ingredients
- 2kg plums, stoned and roughly chopped
- 2kg white granulated sugar
- 2 tsp ground cinnamon
- 1 tbsp lemon juice
- 3 cinnamon sticks (optional)
- Knob of butter
Method
- Sterilise the jars and any other equipment before you start. Wash jars and lids in hot, soapy water, rinse, then place on a baking tray and put in a low oven for 10 mins or until completely dry. If you want to use rubber seals, remove the seals and cover in just-boiled water. Make sure you sterilise any funnels, ladles or spoons you’re going to be using too. Put a couple of saucers in the freezer, as you’ll need these for testing whether the jam is ready later (or use a sugar thermometer).
- Put the plums in a preserving pan and add 200ml water. Bring to a simmer, and cook for about 10 mins until the plums are tender but not falling apart. Add the sugar, ground cinnamon and lemon juice, then let the sugar dissolve slowly, without boiling. This will take about 10 mins.
- Increase the heat and bring the jam to a full rolling boil. After about five minutes, spoon a little jam onto a cold saucer. Wait a few seconds, then push the jam with your fingertip. If it wrinkles, the jam is ready. If not, cook for a few mins more and test again, with another cold saucer. If you have a sugar thermometer, it will read 105ºC when ready.
- Take the jam off the heat and add the cinnamon sticks (if using) and the knob of butter. The cinnamon will look pretty in the jars and the butter will disperse any scum. Let the jam cool for 15 mins, which will prevent the lumps of fruit sinking to the bottom of the jars. Ladle into hot jars, seal and leave to cool. Will keep for 1 year in a cool, dark place. Chill once opened.
This recipe was created by Jane Hornby from our friends at Good Food.
Serve with
I like to serve this jam at breakfast with hot, buttered crumpets or homemade bread.
Because plum jam is slightly tart, it’s excellent for baking as it brings a little tang that balances a sweet dessert or cake. Try easy jam tarts, Swiss roll or easy jam sponge from our friends at Good Food, and switch up the strawberry jam specified for your own homemade plum jam.
This jam is also excellent in a Bedfordshire clanger.
