The company HC Clements, which appears in the first episode of "Cucumber", is also a subsidiary business affiliated with Russell T. Davies' version of Doctor Who (2005). It is the company Donna Noble works for when she first meets the Tenth Doctor in Doctor Who: The Runaway Bride (2006).

The title was inspired by a scientific study into the male erection which divided the erection into a hardness scale consisting of tofu, peeled banana, banana, and cucumber.