The rootstock may make a difference in how young Santa Rosa fruits. We have two trees. One bore fruit when young and the other did not. And can we assume that you get enough winter chill for good bloom? Santa Rosa has quite a low chill requirement, so unless you're right on the coast, you probably do. Do you spray with copper or another fungicide in winter? I think Santa Rosa is one of the less susceptible of Asian plums to brown rot, etc. but if you live in a humid area, that could be a factor. Spray when you spray your peach tree. Thanksgiving, Christmas and Super Bowl time recommended in our area. Copper/dormant oil is a typical choice for home growers. Try summer pruning this year to try to encourage fruiting next year.

Thank you for the advice and reassurance :) I tried it last night ... turned out pretty well, if I do say so myself! It is one of my first jams so I was fairly happy that it worked. I made 8 cups of fruit, and only used 1 package of pectin (which is only half what they recommend) but I figured that plums are a high-pectin fruit apparently and can be used without any pectin ... so I only put enough for the cherries. It "set" really well so I guess that was ok. I used basically the recipe I posted above except only 2 cups of sugar. It is certainly sweet enough like that but I was just worried because the sugar is meant to be the preservative, and I wanted there to be enough to be safe to store. If I used 2 cups of sugar with no-sugar-needed pectin and 8 cups of fruit, how long will it last on a shelf? Regular Jams usually seems to last a couple years, would this reduced-sugar option be less? I used allspice which was really nice with the plums and cherries. Tastes more like a fall jam than a summer one but that's ok ... it will keep till then. Next time I will try vanilla, that sounds incredible too!! Liqueurs are a great idea too, I hadn't even though of that aside from the Red Wine that was in one recipe I found. Thanks! I only had ground allspice but I understand what you mean about the cloudy jam ... mine doesn't seem to be (yet) but I will definitely keep that in mind and look for whole spices that can be removed :) So if I was going to use Sugar instead of Fruit Juice, would I just substitute it 1:1 Cup? The cherries seemed to be juicy enough without much added liquid so I don't think I'd need the juice for liquid. Next up (tonight hopefully) is Raspberry - Lemon Jam. Again, high pectin fruits so will try using 8 cups of fruit and only 1 pkg of no-sugar-needed pectin with 2 cups of sugar. Raspberries are pretty juicy too, I think.

A butter has a lower sugar level but if the plums are very high in pectin the mixture may still jell. It's unavoidable. I did have it happen once and ended up with a spiced plum jam (which is not necessarily a bad thing). Carol

I found a method that works beautifully! Cut the plums in half, roughly, but don't bother pitting or peeling them. Cook according to your favorite jam recipe (the fruit will cook off the pits). When the jam has jelled, pour it into a large-holed enamel colander over a large pot. Use a spatula or wooden spoon to work the jam through the colander, retaining all the pits. Ladle pit-free jam into jars, etc. It can be a bit messy, but it's much easier and faster than pitting all the plums beforehand. Three dozen jars and counting...