Last fall I moved into an apartment with a plum tree in the front yard. I don't know anything about plants or trees or fruit, and now that summer is here there are hundreds of plums dangling off this tree. They're attracting millions of ants, as well as raccoons, possums, rats, and a few bold humans who I've caught plucking from the tree.
I guess I like plums? But there's around a week left until they all fall to the ground and become a horrifying slurry, and I'd rather avoid that.
Any suggestions?
TLDR: Have plum tree, it's bursting with plums, no idea what to do in order to avoid ant apocalypse
Yep, this is probably the best bet. Some other options: ferment them to make wine or pit and freeze the flesh to drop into smoothies or make juice out of on demand.
Not the original commenter, but it's really simple, you just need to mix fruit and sugar in a 1:1, 2:1 or 3:1 ratio and add a splash of water, and bring it to a low boil under constant stirring with a wooden spatula. Once all sugar is dissolved, take it off the heat and stir in some gelatine (powder or sheets - if you opt for sheets, soak them in cold water for 90 secs prior). Keep stirring until the gelatine is thoroughly dissolved as well, then put it into jars, pop on the lid while steaming hot, and chuck it in cold water for a minute to create a pressure seal. Then let it fully cool down at room temperature.
For plum jam particularly, I prefer a bit higher acidity so I'll go for a 3:1 fruit to sugar ratio, but that's your call, really. If you want to add some extra flavor notes, you can throw a handful of cloves in when cooking the mix (just get them out before filling it into the jars), and then after cooking, put a cinnamon stick into the jar right before you throw it into the water. That can remain inside until you first open the jar later.
I'd suggest to experiment around at first with smaller batches to get your preferred mix, and then go all in.
The only thing I would change is instead of gelatin, use lemon seeds, as they will thicken up the jam too, but tend to leave a more pleasant texture. Make sure to boil the jam for at least half an hour too to ensure it is smooth.
Plums contain enough pectin to turn into jam with only sugar and maybe some lemon juice (for acidity) added, though if you're doing this the first time you probably want to add extra pectin. Over here that's generally done by buying sugar that's laden with pectin, in other places you buy the stuff without included sugar, I recommend to search for recipes on your local internet. If you have a plum tree in front of your window someone in your country will know how to turn supermarket ingredients into jam.
Gelatine in jam is, IMNSHO, a travesty. You're not making jello.