I've had fun with a little bit of fig grafting this year, and I look forward to doing some more next year--but with only one exception, it hasn't achieved the results I'd hoped for. I had expected the grafts to really take off and grow much faster than a rooted cutting, and let me sample fruit in the first year. Then, I hoped to air layer the grafted branches and make new plants.
I grafted LSU Scott's Black, LSU Improved Celeste, Panachee, UCR 187-25, Black Madeira, and Violette de Bordeaux onto a UCR 135-15s, using a "modified bark graft" from an online tutorial; all of them "took." (I also tried an experimental graft which proved 100% fatal.) Out of all the grafts, the LSUIC grew very rapidly, produced good fruit, and is currently being air layered. The LSUSB grew nicely, though not as fast, and hasn't fruited. The others are alive but have only put out 3-5 leaves each, and look like they're just getting under way as the season winds down. In other years, my rooted cuttings have grown much faster.
My concern now is how to protect the grafts this winter. It's not unusual to lose some top branches, and usually it's no big deal because even if a tree freezes to the ground, it resprouts from the base. But--if I lose these grafts, that's all she wrote. If you're in an area where there's any danger of frost damage, I'd suggest skipping the grafts. If you really need to save space, you could plant two or three varieties in the same hole, or grow a hedge as some members have done. But if you rely on grafts and something bad happens above the union, you'll have to start all over.