I don't think I ever have, fruit
the cat smears them up and I'm lazy
Tbf I live in a flat and hate heights so would be terrified leaning out to clean the back ones with the massive drop to the busy main road...
of all these people with decent insurance policies and courtesy cars etc. Mine is still held together with an old shoelace and some parcel tape 
I took R for a nice long walk into and around town, popped him down for his nap at 12 (he'd been rubbing his eyes on the way home so I knew he was tired despite last night's epicness) and he's just chatted himself to sleep quite happily. Who stole my non-sleeping grump monster? please please keep that one I like the new version more