Keep this area well caulked to prevent moisture intrusion to the underlayment below. Subarea Be sure the subarea is properly ventilated. Even a subarea with standing water will not have a fungus problem is the subarea is properly ventilated. Make sure the soil does not contact any wood members. Make sure the exterior soil level is lower than the top of the foundation.
Wood deck Make sure the decking is properly spaced to allow water to drain.
Do not install outdoor carpeting. This will virtually insure the deck stays wet in that area. Elevate large planters on bricks. Eliminate earth to wood contact. This is commonly found at the base of steps and support posts.