It’s the time of the year when our damson plum tree is laden with tiny tart plums that suddenly ripen over a few hot days. Last week, or was it the week before (!), I picked around 6kg of plums to make jam. The plum-ginger-lime jam is always a favourite with my family, the kids love it on their toast, so half of the plums went into making a new batch of that one.
With the other half, though, I wanted to try something new. I came across a recipe on the blog Eat the Love for a strawberry-plum-rosemary jam which sounded intriguing, and that sent me on a Google-Pinterest hunt for more plum-rosemary jam recipes. In the end I grabbed a little of this and that, and came up with my own version, using fresh rosemary from my garden and a lemon from a friend’s lemon tree.
I was mindful that rosemary can be quite overpowering so I took it out after the initial cooking of the plums. It’s given the jam a wonderfully subtle herbal note, a hint of rosemary that complements the tart sweetness of the plums. I wonder how it would go on scones with a bit of crème fraiche instead of double cream?
Out of 6kg of plums, I now have around 20 jars of jam, in various sizes and two flavours. Half of them are for the school fete, the rest are for us. And I’ve still got a kilo of plums to play with, might be time for a batch of plum ice cream!
Put whole plums, lemon zest and juice, whole rosemary sprigs and water into large non-reactive pot.
Bring to boil over medium-high heat and reduce to simmer for 10-15 minutes until the plum skins have split and the flesh is soft.
Remove from heat and mash plum mixture with a potato masher. After 10-15 minutes more, remove the rosemary and discard. Allow to cool and then remove plum stones (see notes below).
Bring plum mush back to the boil over medium-high heat. Add sugar and stir until dissolved.
Allow to boil vigorously, stirring occasionally, for 20-30 minutes, until jam “jells” (see notes below). Skim off any scum that forms and remove any plum stones that come to the surface. When it is ready, take off the heat and let it sit for 5 minutes or so while the jars are set up.
Pour jam into hot sterilised jars and seal (see notes below). Recipe makes about 3-3.5 L of jam.
1. I have found the best way to remove plum stones is to use a slotted spoon to scoop up plum mixture and a smaller spoon (or clean fingers) to pull out stones. It’s a tedious job, but stones that are missed can usually be pulled out when the jam mixture is boiling—they seem to get tossed up to the surface by the rolling boil. If necessary, the stewed fruit can be refrigerated overnight until ready to perform the next step.
2. I use two methods to determine when my jam has jelled. First of all, put a couple of saucers in the freezer before starting to make the jam. Then, I regularly scoop up a bit of jam onto the wooden spoon and then slowly tip the spoon sideways to see if the droplets run together to form a “sheet” of jam. When that happens I grab a saucer from the freezer and drop a little bit of jam onto it. Back into the freezer for a couple of minutes and then push your finger into the jam—when it wrinkles up it has jelled. Better to underdo it slightly and have slightly runnier jam than overcook it.
3. I sterilise my jars and lids by washing in very hot soapy water. The jars are then placed upright on a baking paper-lined tray and popped into the oven, which has been set to 120ºC or thereabouts. I remove the jars just before I pour the jam into them, then screw the lids on tight and turn them upside down to cool down.