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.
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.
According to his Oscar speech, 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.
Since Thora Birch was barely 17 at the time she made the film, and thus classified as a minor in the United States, her parents had to approve her brief topless scene in the movie and they and child labor representatives were on the set for the shooting of it.
Wes Bentley was the first actor to read for the part of Ricky, and was asked to do the scene where he describes his reaction to the plastic bag; the casting director felt that although she had read that scene numerous times, his reading was the first time she felt she understood the meaning of it.
The tagline and important theme of the film - "...look closer" - can be seen in Lester's cubicle at work. It was simply something a set dresser had put in, and director Sam Mendes noticed it while editing and suggested it be used for the poster.
Chris Cooper was the last actor cast - virtually when rehearsals were beginning. When he first read the script, he found the character infuriating, thinking: "God, do I want to spend so much time in this character's head?" He remembers, "Then I started making excuses... I said, this is such a negative script, I don't like this and that." His wife finally told him he was "frightened of this script and chances are because you're frightened you should do this part"; his response was that he "knew, really immediately, that she was right."
The scene where Lester is putting in an application for the counter job at Smiley Burger was actually shot at night, but it was later fixed to look like day. Notice that neither Lester nor the burger kid have shadows on their faces from the sun.
Director Sam Mendes storyboarded extensively, based on his plan to use three visual styles - a very formal style for the bulk of the film, augmented by a more graceful style for the fantasy scenes and a handheld look for the video footage.
On the DVD's Audio Commentary, Alan Ball reveals that he came up with Angela's line "You're defending him, you love him, you wanna have, like, ten thousand of his babies" during an U2 concert after hearing a fan screaming to Bono Vox that she wanted to have ten thousand of his babies.
The first day-and-a-half of filming - including Carolyn's open house scene - had to be thrown out after the film turned out too dark, making Annette Bening almost impossible to see; director Sam Mendes and cinematographer Conrad L. Hall concluded the problem had been their overly polite relations, and agreed to be more open with one another.
Alan Ball originally intended to write a script about Amy Fisher, the "Long Island Lolita" who shot lover Joey Buttafuoco's wife Mary Jo Buttafuoco in 1992; but each successive draft of the script drifted farther away from that story, until it essentially disappeared.
The filmmakers made an effort to avoid any specificity in the film's locale, in favor of a more generic setting. However, the area codes in Jane's phone book are 312, which is the area code for Chicago, and the paper in the Burnhams' kitchen appears to be the Chicago Sun-Times. Also, the lawn signs for both Carolyn and Buddy have phone numbers with an (847) area code. The (847) area code serves the northern suburbs of Chicago, Illinois. On the other hand, the license plates in the film are not Illinois plates; the plates only identify "The Primrose State". Besides, as Lester is driving and listening to "American Woman", he can be seen driving through Burbank, CA - The reflection of the Disney Channel building in Burbank can be seen clearly as a reflection on his windshield.
The aerial shots over the town were filmed above Sacramento, California. The crew originally wanted to use San Jose, California, but its police department wouldn't allow their helicopter to fly below 300 feet due to noise disturbance; the crew had hoped for a 100-foot height. However, the same 300-foot height limit was imposed in Sacramento.
When Lester and Carolyn are driving to the basketball game, Lester complains about missing a James Bond marathon on cable. Sam Mendes, who directed this film, would later go on to direct the James Bond film Skyfall (2012).
While driving home from the shooting range, Carolyn listens to Bobby Darin's rendition of "Don't Rain On My Parade." 5 years after the release of this film, Kevin Spacey produced/wrote/directed and starred as Darin in the biopic Beyond the Sea (2004).
In the script, Lester was supposed to go ahead and have sex with Angela, but it was decided that it would be better to have him stop just short of doing so - in spite of the filmmakers' concerns that they might be making the change out of uneasiness with having the main character actually go that far.
Another version of the script involved Ricky and Jane being arrested and convicted for the murder of Lester. The main evidence is the video Ricky made of Jane offering him $3,000 to kill her father, which we, the viewers, find out was a joke immediately after Ricky turns off the camera, one second too late for the defense. It also involves Mrs. Fitts finding her husband's bloody clothes, and hiding them immediately after.
After the film was complete, director Sam Mendes and editor Tariq Anwar decided to scrap a short fantasy opening and the lengthy epilogue in which Jane and Ricky are tried for Lester's murder, choosing instead to increase the three teens' screen time throughout the film; many of the cast and crew were caught completely by surprise when they saw the finished film.
When the funeral caravan passes by Jane and Ricky, he tells her that looking at a dead homeless person was like God staring at him, and he could stare right back. At the end of the film, when he sees Lester's body, he momentarily stares into Lester's eyes, fixated as if looking at God.