In this version (YouTube) of "Sing", Bob and Luis are in the arbor which has a fence with what looks like palm tree leaves painted on it.
Does anyone know how long that set lasted? We know this version of the song has an EKA of Episode 0543 (season 5) and that Luis first appeared in season 3; I'm trying to figure out if there's potentially an earlier appearance.
A quick look through some clips of the end credits on YouTube shows that the painted palm tree on the fence was present from seasons 2 (YouTube) through 8 (YouTube), and was removed by season 9. (YouTube)