mini golf carpet has molded outside

Spray it with wd40 you can buy it at most hardware stores

Why would you want to spray carpeting with oil? That makes no sense.

Mold requires moisture. The carpeting is getting wet and not quickly drying out.

What you want to do is prevent the carpet from getting wet and that will resolve the mold and curling problem.

Do you place a tarp over it at night and during poor weather to keep it dry? Once it does get wet, you might try hanging the carpet on a railing for good air circulation and quicker drying.