Higgins (John Hillerman) is correct; there is so such thing as a black orchid; it's really an extreme dark shade of purple. There's also no such thing as a black rose. Flowers lack the genetic ability to be truly black only dark shades of colors that appear to be black.
First episode in which Magnum is referred to as Thomas, rather than Tom, as he and others called him in previous episodes.
Episode director Ray Austin has a small part in this story. He also plays another small character in the fifth season episode "Ms. Jones", another episode which he directs.
Judith Chapman, the actress who plays Louise DeBolt Jackson in this episode, also plays additional characters, Sara Clifford and Lisa Page in "The Woman on the Beach" of Season 2 Episode 3.
Higgins properly identifies the Rolls Royce as having a Gurney Nutting Sedanca body. This particular example is a 3 position drophead coupe of which only a handful were built. In its day it would have been driven by its owner and not by a chauffeur as depicted in this scene.