How often should i bathe my dog?

i have a bichontese(bichon frise maltese mix)odviously shes white i get her groomed about once a month(sometimes every 6 weeks ) but shes a very playful frisky dog she loves playing outside so she gets dirty fast and starts to stink quickly(and like i said shes white so you can see it), should i bathe her in between her grooming?