outdoors you cannot control the humidity,my buddy loses his outdoor crop to mold 3 years running he since stopped growing outdoors i know of no way outdoors to control the mold,maybe someone here will....i would cut the mold off or even that particular bud,and monitor your plants very closely!!! if your outdoors your almost ready to harvest!!! if you see it spreading you may have to harvest a bit early.. keep a close eye on your babies...