try the recipe again and if the jam is really hard try using at least 1 more cup of prepared fruit than the recipe calls for. If the jam is still really hard, try using even more prepared fruit next time. I have the same problem with some fruit, store-bought blueberries especially.

I was concocting a recipe for mango jam using commercial pectin. I used the peach recipe, substituting peeled crushed mangoes for peaches. The jam was to hard for my taste. The next batch I put up with (I think) 2 extra cups of prepared mangoes--viola! Mango jam--not hard jelly.