The "Carry on..." debut of Joan Sims. Sims became the longest serving female member of the "Carry on..." team, appearing in twenty-four of the series from 1959.
Kenneth Williams kept falling asleep, due to the combination of warm studio lights and acting on a bed. When Gerald Thomas would wake him up, Kenny would swear blind that he wasn't asleep. So the next time it happened, Thomas put a sign around his neck, and took a photograph. When Kenny tried to wriggle his way out of it again with protestations of not being asleep, Gerald showed him the photograph - apparently Kenny's language became very colorful.
The closing visual joke with the daffodil was so popular with American audiences, that plastic daffodils were given away at theatres screening the film.
"Carry on..." regular actor Bernard Bresslaw was not cast in this film, but his legs and feet did make an appearance during the scene where Ted York (Terence Longdon) is having a bath being bathed by Joan Sims. Longdon's legs were thought to be too thin, so Bresslaw acted as a body double for this purpose.
In one scene where the Colonel is seen placing bets with the medical orderly, Wilfrid Hyde-White changed the name of the horse from the scripted "Bloody Mary" to "Rambler", which Hyde-White had backed earlier in the day. Harry Locke visibly reacts to the name change, but doesn't spoil the take.