I've started bushes directly adjacent to buildings, rivers, trees and cliffs with no issue. If you can dig a spot it seems to support bushes. Fully grown bushes can be moved without any energy too, so it's easy to toy around with placement.
All the TT occurs on my end so your turnips would be fine but you'd have to wait idk how long since moving out is kinda random. Don't wanna keep you up just for a trade lol