While I love the idea of preserving berries and other local fruit by turning them into jam, I often find the taste way too sweet, due to the amount of sugar required to make the stuff gel. Except for the tartest fruit, the flavor is obscured by the sweetness. Now I think I have found the solution. 

"Pomona's Universal Pectin," like Certo and Sure-Jell, is made from citrus pectin, but it is "low-ester" - difference explained here - and requires calcium as an activating agent instead of a lot of sugar. There’s a little packet of calcium and instruction for its use in the box with the pectin. The instructions are simple and allow for much more variation than the high-ester pectin does – even making suggestions for coming up with your own recipes.  Because our blueberries were quite sweet, I used the lower range of local honey called for – ½ cup to four cups berries (sugar, agave, maple syrup, etc. could have also been used). The Sure-Jell recipe calls for a whopping 4 cups of sugar for the same amount of berries. 

The less-sweet Pomona version was quick and easy and turned out absolutely delicious. So much more of the actual taste of blueberries is present in the final product. And I love the fact that, except for the pectin, the jam is 100% local. 

In Gainesville, you can buy Pomona's Pectin at Ward's.