Unfortunately mold is something that we have to deal with. Mold is everywhere, all the time, but only under the right conditions can it cause a threat. While mold itself is not always bad (think of it as nature’s way of recycling), it can be detrimental to older decks made of soft wood and composites.
Mold only needs a few things to grow: food, such as dirt and pollen, water, and favorable weather conditions. When these three elements are all met, the mold begins to have a feast on whatever it’s sitting on.