When do I need to get a base grind for my snowboard?

I got a new board at the beginning of this season, and have probably rode it about 20 days, in Pocono weather conditions, which seem to beat up the base and edges quite a lot. i have made a few base repairs with p tex candles, im not sure if that really matters. Should i get a base grind? ( I want my board in top shape since im going to park city later on.) If this isn't enough information, please let me know what a good indication of needing a base grind is. I hope someone can help. thanks in advance.