There is a restroom at the entrance to the farm but no bathroom once you are near the origional farmstead buildings.
I recall there being nice, newer restrooms. The day we went (a Saturday) there was a woman in the museum kitchen who was super helpful explaining things about the farm. Also several people in the office and store, all very knowledgeable. Enjoy your visit; we loved it!
There is a modern bathroom at the visitor center disguised as a barn. There is 1 porta potty in the historic farmstead on the Old Gainesville road going towards the cane field behind a fence.
Thanks! Your answer is awaiting moderation.