Potatoes require less water than most plants in a typical garden. You really need to make sure that you don’t rot the potatoes or cause fungus on the plants. I like keeping the watering down to about once per week. However, doing so when planted with water hungry plants is nearly impossible.
My solution is growing potatoes in tall sturdy buckets. Potato buckets allow complete control over water, sun and weather. And, repurposing buckets as potato buckets is a great use for old pales left over from grinding wheat into flour.