Yes, you can combine them. I would follow the recipe for the fruit you use the most of. If equal amounts, read both sets of ingredients and keep the ratios the same. With the fruits you listed, you shouldn't have any problems as they all set well. Jam is low risk if proper canning methods are used. The worst that can happen is that it doesn't set (then we call it syrup), or it sets too firmly (heat and use as a glaze or still as jam). Deanna

Wife's recipe is simple. She says she just took the rhubarb jam recipe and the blueberry jam recipe off the pectin box insert and combined them. 3 cups of diced rhubarb 3 cups fresh blueberries 1 box of Ball No-Sugar pectin (or you could use the low sugar pectin) Sugar to taste (she used 2 cups so it would still have a pucker factor and we don't like really sweet jams) Mix and cook all until it begins to thicken, bring to a boil, hard boil for 2-3 mins., jar and process. Dave If you don't want a low-sugar jam you can just use the Rhubarb Strawberry Jam recipe at NCHFP and sub blueberries for the strawberries.

I agree that the 1/2 cup of lime juice is sufficient, especially when compared with the Ball recipe. The NCHFP is a wonderful reliable resource but it's not the only game in town. However, even with a "reliable" blogger, I always double-check recipes and recommendations against other sources. Even if the recipe is safe, it's so easy to mis-type ingredient amounts or times and throw a recipe off. The Ball Blue Book has occasionally had errors; how much easier for someone who doesn't have a staff of editors. In preserves I don't generally use the bottled citrus juice and, in fact, in a reliable recipe from the NCHFP, the BBB, etc. if bottled isn't specified, I don't use it. I know in salsas, tomato products, pickles, bottled is always specified for good reason. But if it's peach jam, I don't worry about it. While it's always the safest, most conservative option, with sweet preserves I use fresh. However, if I were making banana jam or some similarly low-acid concoction, I would go with the bottled. I confess for me the issue doesn't arise in most cases. I tried tomato jam once. Never again. It just isn't a favorite with me. Carol

in case you guys were wondering what it came out looking like, here's the pic. by volume it was probably 3/4 pineapple (this is before the sugar went in), but the color would lead one to believe it was mostly blueberry. I think it came out wonderfully. with the addition of one carolina reaper pepper, it's wonderfully spicy too. excellent addition to a morning bagel if you're like me and aren't a morning person. it wakes you right up. 1 large pineapple, 8oz blueberries 1 tbsp lime juice 1 carolina reaper pepper 3 cups sugar 3 tbsp ball NSN powder pectin yield: 3 pints I threw the pepper, the blueberries, and the pineapple in the blender and blended til smooth, from there I followed normal jam making procedure, and boiling water processed for 10 min. it set very well, I am quite happy with the consistency and texture. I also made another spicy pineapple (no blueberries), spicy apple spice, spicy chocolate strawberry, and non spicy strawberry jam for my wife, who can't handle the spicy jams. with those and the hot sauces, I think I have most of my christmas list taken care of now.