As a general guideline Spruce skews towards watering longer, but less often. This is how the experts recommend watering is done.
Watering in this manner promotes deeper roots and more drought tolerant plants. It also allows the soil time to dry and replenishes the oxygen in the soil. All good things for your plants.
If it’s appropriate for the soil type, Spruce also breaks the watering time into cycles, which helps reduce runoff and evaporation.