You discuss the use of the word "businesses" in the chapter, meaning the various aspects to a permaculture operation, and I agree it feels a little clunky. Paul then suggests the word "crops."
The word I've heard numerous farmers, etc. use is "enterprises" -- which I feel implies businesses within the business. So apple trees, broilers, veg, lumber, all different enterprises on the same property. Another word that came to mind was "ventures."