Director Sir Sam Mendes designed the two girls' look to change over the course of the film, with Thora Birch gradually using less makeup and Mena Suvari gradually using more, to emphasize his view of their shifting perceptions of themselves.
When Lester throws the asparagus, he was supposed to throw it on the floor. The reactions of Annette Bening and Thora Birch are genuine.
According to his Oscar speech, screenwriter Alan Ball was sitting at the World Trade Center plaza when he saw a paper bag floating in the wind and was inspired by it to write the film, which was originally conceived as a stage play.
The title of the film refers to a breed of roses that, while pretty and appealing in appearance, is often prone to rot underneath at the roots and branches of the plant. Thus, the tagline "... look closer" tells the viewer that when they look beyond the "perfect suburban life", they will find something rancid at the root.
Kevin Spacey improvised everything he does in the car while his character is stoned and singing to "American Woman."