your a tall dude to let that bother you!
if its not broke dont fix it.
jokin apart thats another area I want to make sure is mint.:thumbs
sure some one can help
Mines been like that for years, when weather dries up a bit it'll lose the green. Don't worry about it it's fine. I've not been bothered by it but I guess you could run some neat washing up liquid along it for a day and then rinse off, that should kill the moss.