Yes, by coating your sail properly, mold will be much less likely to adhere to the sailcloth. Of course, never store the sail wet, to prevent mold as much as possible.
Prevention is better than cure!
It is best to provide a new sail with an additional coating right away.
Of course, the tarpaulin has already been provided with a protective coating by the manufacturer. However, this protective coating disappears fairly quickly, especially through UV radiation. In many cases the protective coating has disappeared after one season. You will notice that, because the sail stays wet longer, gets dirty faster, is green and maybe already moldy.
Sail & Spinnaker Coating is very resistant to UV radiation. A sail treated with this protective coating will stay clean longer.