How to make
Wash the melon and cut it into small cubes. Peel the plums and cut them into small pieces. They will add more taste to the melon.
Pour the sugar in a pot and put the jam on the stove. Do not add anything extra.
The melon releases enough liquid, which needs to thicken. Stir it frequently and boil it over medium heat.
After 1 hour add the citric acid and leave it to boil for another 5 minutes.
Then fill up the jars while it's still hot and leave it to cool.