If you can POSSIBLY include it, Mary Jo's Cloth Store would be the most memorable stop of your trip. They have entire tables of ONE color of cotton blenders, rows and rows and rows of novelty prints, and huge specialty sections of batiks, solids, etc. You will be stunned and, her prices always seemed very reasonable to me. A little detour to this shop will make your entire shopping trip! You would need to take Highway 74 east off of I-26 below Hendersonville, NC to I-85 to Gastonia,NC. She's located off the Cox Road exit. When you finish shopping, get back on I-85 east to connect with I-77. I believe there is a completed "beltline (I-485?)" so that you can miss Charlotte. You connect back with your I-26 route in Columbia, SC and on to Charleston. It isn't much of a detour and when will you ever get the chance to see this amazing array of quilting choices?
Things to consider if you choose to visit Mary Jo's: Her hours are 9-6 and she's open Sunday afternoons as well. If you can go on a weekday, it's better shopping. Plan on giving yourself lots of time. There is much to see and choose from. Whether you have enough time or not, you will always dream of going back! I know I do! I have shopped for quilting fabric from Alaska to Key West, Nova Scotia to California and this shop is the best I have ever been in.
On a personal note, I think your UP part of Michigan is absolutely amazing! My visit there was just delightful in every way! Enjoy your trip wherever you go.

It's Probably 45 min.off your route but zipping over to Hearts to Holly in Charlevoix would be well worth the trip.
There is a nice shop in Indian River,also.

I have an app on my smartphone from Quilters Club of America that is GPS enabled. Wherever you want to go, it will give you a list of shops. We are planning a trip to Wyoming this spring and I already have my itinerary mapped out. Have a great trip!

I was going to suggest Fabric Shack in Waynesville also. Also in Loveland OH is Quilters Studio, they have tons of batiks and some Aboriginal fabric. Silk Road in Cincinnati also has some really unique fabrics you don't see elsewhere. You could spend a whole month traveling to Florida to hit all of the good shops on the way.

I don't know if you've seen the news or when your trip is planned, but there is a section of I-75 that is closed due to rock slides. I read that the closure starts at Jellico (near the KY-TN state line) and continues down through Caryville. I read that it's expected to reopen on 3/21.

In Jacksonville, FL, there is Lady Bug Quilt Shop, I have stopped there recently, wonderful fabric selection, had a long chat with ladies, love it

There is a book you can get (try Amazon) that has all of the quilt shops listed by state. That would be a great resource for you on a trip that long,. Have fun, and I hope you can stop at a lot of them

Yes, Julie, we did see that there is a section of 75 closed. Looks like they have a detour set up. I'm glad we weren't driving in that area when it happened! Thanks for the "heads-up".

Mary Jo's is well worth the visit. I shopped there for my bargello fabrics (had to have 20 different fabrics) and found all but 4 or 5.

If you get anywhere near Charlotte Michigan, check in at The Hen House.