KandKsmom, as I am sure you and your son have begun to realize, most B.Arch programs are GRUELING. I have heard nasty rumors of cots and sleeping bags stuffed under drafting tables, sleep depravation that goes on for weeks, and caffeine-laden meltdowns. It was refreshing to hear the Tech program director (Scott Poole, I think his name was) describe a process of "slowness" taken by the faculty there. He had taught for many years and seen students at many programs be assigned projects that professionals could not reasonably finish in such time constraints. He invited us to search the rows of drafting tables to find any trace of a pillow or sleeping bag or anything, and we found nothing of the sort. I suppose it is not THAT different from any other program, but this concern for students and their course of study struck me as very considerate and professional. I think it will not be long before other programs follow suit.
But since you are looking in a more landscape direction I might suggest getting any general degree in architecture or art/art history (BA or BSA or BArch, whatever) and then getting a masters specifically in Landscape Arch as I think many successful professionals have taken this route. With this in mind, it might open up some more choices, but I completely understand your son's desire to go ahead and get such a degree as an undergrad (which seems to be a safer option).
As for Auburn, you are right that it would be a long way away, but I think they'd love to see kids from out of state. Scholarships, like at UVA, are harder to come by there, though, and I don't specifically know how the study of landscape architecture would fare. It just happens to be a safety school for me and thought I'd recommend it.
And while we're on the subject, I could also use a little help if you don't mind:
Good Choices?