There is no rule to this concept - It would depend on many things.
1.How dirty your dog gets, if not that much may be you would like to spunge him.
2. Where you like and hows the climate of that place, eg. if you live around Sea and too much of humidity you would like to bath your dog few more times if you are not living in a climate which is not that humid.
3. If you live in North - in few weeks Winter would settle down, its advisiable to get your pet into water.
Remember after bath - get your pet in Sun - let him run around - this would help your pet to dry out the hairs and it would be fun.
There is no simple or thumbrule to your question.