I picked red grapes at Pomegranate Alley Community Garden (with permission) and supplemented them with Catawba grapes from my backyard. After giving these grapes a bath, I turned them into jelly!
For grape jelly recipes, I compared multiple sources. The National Center for Home Preservation offers a traditional recipe...with a traditional heap of sugar. I've gotten excellent results previously from using SureJell's low sugar pectin, which comes with recipes inside the box, but the grocery store where I usually find it was all out. So I picked up some Ball low sugar pectin at another store and used Ball's online pectin calculator to figure out proportions of fruit, pectin, and sugar. For additional guidance, I referred to pickyourown.org because they walk you through each step with helpful advice and photos.
A note about extracting juice: maybe using a juicer works for dark purple Concord grapes, but it does not work for red grapes. I know because I tried it. The resulting juice was an unappetizing dull greenish-brown because the juicer separated the skins from the pulp. It tasted fine, but looked hideous. In the above photo, I extracted the juice following the stovetop method of simmering, mashing, and straining, which resulted in the pinkish-purple juice you see here.
But what about layering in other flavors to make a more sophisticated, grown-up grape? How about balsamic vinegar, cinnamon, cloves, and black pepper? Yes! ...even though that recipe is for a jam, not a jelly, it served as inspiration to make a jelly reminiscent of mulled wine.
I'm not ready to share a final recipe for this jelly yet because I might tweak it some more for my entry in the DC State Fair. Nevertheless, I hope I have given plenty of hints for how you can make grape jelly at home to suit your tastes.