My in-laws have a plum tree. Unfortunately, the bugs started to get the plums, so they picked the entire tree too early. They were REALLY sour! Too sour to eat plain. So, my husband and kids decided to can some with sugar. There was a lot of juice left in the pot, so I added some pectin and made jam too. The jam is delicious! We haven't tried the canned plums yet, but based on the taste of the jam, they will be good.
We only had 1 1/2 jars of jam, so we didn't can it. The half jar is almost gone already! It tastes like tart cherry jam, yum!
If we don't like the canned plums, we will turn them into jam!
Here is a recipe: Plums in Syrup.