Question: In multiple episodes we see a box hanging just inside the barracks door. What is that? It is mostly blue, and appears to have flowers or something painted on it.
Chosen answer: In different episodes of "Hogan's Heroes, " the arrangement of items in the barracks varies. Sometimes there is a sink on one side of the door. Sometimes there is a chest of drawers on the other. I have seen episodes where a hanging box is there, as you describe. To my eye, the decoration appears to be a kind of camouflage design. I had assumed it was where mail was delivered to the prisoners. It could also be a storage for small items, such as a medicine container. I don't recall ever seeing it opened or otherwise used. Normally, in situations like this, when questions arise regarding set pieces, set decoration or costumes, I attempt to look up the show's crew members IMDb.com to pose the question to the source (when I can find them on, say, Facebook). In this case, however, all of the gentlemen responsible for set decoration on "Hogan's Heroes" have since passed away.
I have the series on DVD, and have been able to scrutinize the blue box. It is a decorated holder for the long matches used to light the stove. Occasionally, you can see part of the word 'matches' through the slot on the side.
Answer: After careful inspection, the aforementioned box is a decorated holder for the boxes of long matches needed to light the stove.
Movie Nut