On several waxed cheeses, I’ve had mold grow under the wax while the cheese is aging. What are the potential causes?

1) The wax did not fully cover and protect the cheese. There are pinhole bubbles/gaps in the coating. Make sure the cheese is well coated.

2) In one case, I dropped a cheese on the concrete floor of the basement and the existing wax was damaged and some came off. So, I simply heated up the wax and dipped the cheese into it a couple of times to recoat it. This is the point at which the mold started growing Obviously, the cheese got contaminated when I dropped it. Lesson? The cheese must be clean before waxing.

3) Other possible causes: the cheese rind is not dry and well cleaned prior to waxing.