Here's the index entry from The Indiana University Sheet Music Collections:

Title: Grass is always greener
Title: In the other fellow's yard
Composer: Whiting, Richard A.
Lyricist: Egan, Raymond B., 1890-1952
Performer: Jean Granese
Publisher: Jerome H. Remick & Co.
Place of publication: New York
Date of publication: 1924
Call Number: M1 .D48 Box: 216 Item: 050
Performance Medium: Piano and Voice (with lyrics)
First Line: Why do you wash your windows said Misses Haggerty so I can watch
Chorus First Line: Sure the grass is always greener in the other fellow's yard
Genre: Popular song
Subject term: Spring/Springtime

According to The Red Hot Jazz Archive, there were early recordings by the Original Memphis Five and by the Fletcher Henderson Orchestra.