The opening credits are set to an upbeat version of the theme from "Taxi Driver"
This is the second time Jon Hamm is interviewed on Between Two Ferns. The first time (in 2010) the chyron says "Jon Ham, Actor, The Mad Men "
When the shows are delivered to Will Ferrell, they are given to him on 20-minute U-Matic cassettes, a video format used in the 1980s.
According to director Scott Aukerman, all of Ryan Gaul's character's t-shirts were custom made, as they had to be unique enough to be interesting, but not funny enough to be distracting from the scene.
There are actually many types of ferns in this film. Most often Zach is with an athyrium filix-femina, the lady fern, or the highly popular Boston fern, nephrolepis exaltata.