During season four and five, writers noticed the chemistry and enjoyment on-screen between Mary-Louise Parker and Justin Kirk, so they decided to increase the Nancy/Andy dynamic, by writing them more scenes together.
Alanis Morissette was a huge fan of the show, and asked if there was any role she could play to the producers. At the same time, Jenji Kohan was coming up with the character of Audra, based on a real friend of Kohan, also named Audra, and offered it to the actress and singer.
According to Jenji Kohan, twins Amanda Pace and Rachel Pace would be slightly envious of each other, because one was playing the twin who got to wear make-up and hair extensions, so to keep them both happy, they would take turns in playing the characters.
A running sound gag is heard whenever anyone (especially Nancy) is sipping a drink through a straw. The noise heard is what one would hear when a drink has gotten so low that air begins to go up the straw. This occurs regardless of the level of the liquid.
For most of season seven, Jennifer Jason Leigh was doing a play in New York City, and wasn't available, so the writers came up with the idea of having her character appear in video chat sessions. She filmed those at her house, during breaks from the play.
On several DVD audio-commentaries, creator Jenji Kohan reveals how the season finales of the show are influenced by some genre or specific directors she loves and thinks about when writing those episodes. Season one was a nod to The Godfather (1972), hence the title of the episode; season two was Quentin Tarantino, the episode ends with a bunch of characters pointing guns at each other; season three was Robert Altman and his ensemble pieces, with lots of subplots crossing; season four was Sergio Leone and the spaghetti-western, with big close-ups of the actors; season five was Pedro Almodóvar, hence the title of the episode; and season six was Alfred Hitchcock, which is actually why Kohan herself makes a silent cameo in the episode.
Regular cast members Alexander Gould and Elizabeth Perkins voiced characters in Finding Nemo (2003), as title character Nemo and Coral, Nemo's mother, respectively. In season four, they were joined by guest star Albert Brooks, who portrays Gould's grandfather on the show, but plays Nemo's father, Marlin, in Finding Nemo (2003).
From seasons four to seven, the intro sequence was replaced by small clips, where the viewer would see things that were prominent later on in each episode, and that featured the name of the show and its creator. Every writer would come up with the one for his or her particular episode.
Justin Chatwin was intended to be a series regular as Nancy's sidekick, but due to scheduling conflicts, he never made a final deal. Justin Kirk therefore joined the cast a few months after the pilot, to fill the void.
The book Rejuvenile by author Christopher Noxon has appeared several times on the show. Noxon is married to series creator Jenji Kohan. Noxon was also the music supervisor for season one and appeared in the pilot episode as a bear hunter.
Lindsay Sloane was a huge fan of the show, and considered the role of Maxeen perfect for the kind she wanted to play, at that time in her career. But, in retrospect, she regrets taking it, because she found out she was pregnant the day before she started shooting, and felt disconnected in the part, because she was disconnected in her own body. She's said she thinks she didn't line up enough with what they wanted that part to be. She couldn't be on the season finale, and her character was written out.
The Shield (2002) is mentioned as a favorite show among some of this show's characters, and several guest stars from "The Shield" have had guest appearances on this show, including U-Turn, Guillermo, and Mermex.
Between seasons of the show, creator Jenji Kohan made a pilot called Ronna & Beverly (2009), also for Showtime, co-created with Jessica Chaffin and Jamie Denbo. The network eventually passed on the project, but Kohan not only used both actresses on Weeds, but also Olga Sosnovska, who also worked on the failed pilot. Chaffin played Cracklynn in season four; Denbo played Raylene in season five, and Sosnovska played Zoya in season seven.
On the soundtrack for season one, the song "David" by the singer Nellie McKay is playing when Doug is smoking a bowl in his mini van during the soccer game. Flash forward to season 6 episode 6, the song that is playing outside the Hungry Kuntry Buffet when Ignacio is saying his goodbyes to Shane, is a song called "If I Ever Had A Dream" which is cover sung by Nellie McKay.
Justin Kirk and Mary-Louise Parker both starred in the Emmy acclaimed HBO television mini-series, Angels In America. Mary won an Emmy and a Golden Globe Award and Justin was nominated for an Emmy. In the very first episode of this show Justin calls Mary's character Harper, "Nancy Drew." Two years later on "Weeds", Andy's character would call her "Nancy Pants".
Jenji Kohan came up with the characters of the three brothers that work with Demetri, based on the Hanson brothers of Slap Shot (1977), because Pablo Schreiber wasn't available for the season seven finale, and his character's absence had to be explained somehow.
Jenji Kohan explains during the DVD commentary, that the decision of literally burning down Agrestic, and moving on to another story-line, was due to the fact that the writers were getting bored of writing suburbia jokes. Mary-Louise Parker was particularly pleased with the idea of killing the original premise of the show, having said loving taking risks when it comes to her acting.
Jenji Kohan once stated that they tried to get Justin Chatwin to reprise his role as Josh Wilson several times throughout the years, but he was always booked. Knowing it was their final chance, Kohan sent a text message to Chatwin directly and asked him to be on the series finale. Having done that, Chatwin appeared only in the first and final episodes.