Can mould grow in a cool dark place in the presence of salt?

Question

Could the salt actually attract water and encourage mould growth?

If not, couldn't salt be useful in making hollow areas mould-proof along with making sure they are well sealed?

Answer 1

While many of the common household molds cannot grow in a salt environment, there are many molds and fungi that do quite well in salt water.  Salt tends to dehydrate tissue, so the water that it attracts will actually draw water away from the mold.  But when you make it difficult for the common molds, you just leave room for some of the more uncommon ones.  The best defense against molds that I know of is Copper Sulfate, as this not only tends to dehydrate molds, it actively interferes with the mold life cycle.  You will find areas of the world where copper cladding is used in construction and trim (like the Statue of Liberty) and you will find no mold on it.  The green tint comes from the oxidation of the copper, not mold or fungi.