As gourds dry out/cure, they will get modeled with mold. It is not attractive to look at, but is a normal part of the process. I myself like the way the mold spots leave a unique texture look on the gourds surface, as part of my art. Other artists do not, and are able to work around this. If you do not want the mold patterns, you can 'green peel' yours gourds, just after harvesting, by scrapping the outer waxy layer off the gourd skin, and immersing it in bleach. You will need to check on them periodically for mold, and redip them if need be. Also, snow will not hurt them. Come spring you will want to check them for signs of cracking, shriveling, and rotting, and get rid of them accordingly.
How long it will take to harden off, cure, or dry out your gourds, depends on the size of the individual gourds. It can take a few weeks, to over a year. Generally there are a few tell tale signs that let you know the process of over.
- Look for brownish skin under the moteled mold
- Seeds will shake loose, like a rattle
- The gourd itself will feel hard