This jam was delicious! I had to substitute ground ginger for fresh and orange peel for the lemon peel because that was what I had on hand. I had reduced the amount of suger due to preference but next time I will reduce it further. It was still a bit too sweet for me.
This jam is AMAZING! I made the jam yesterday and brought it to a family gathering with a loaf of homemade bread - there weren't any leftovers! They liked it so much, I am making two more batches today! The only things I changed are that I reduced the ginger by 1/2 (wanted the taste of the plums in the forefront) and omitted the lemon peel (didn't have any lemons).