Answer: It's always a good idea to cover the roots with soil when planting. Otherwise the roots will dry up and eventually die. Sometimes plants in containers will produce surface roots because their roots are too crowded and you may see a network of roots on the top of the soil. These roots should be covered with soil when planting in the ground or when repotting into a larger pot. As for watering, about one-inch a week is usually sufficient for landscape plants. What you might want to do until you get a feel for how thirsty your plants are is to water thoroughly and then wait 3-4 days and dig down into the soil. If it is still moist 2" below the soil surface you won't need to water for another few days; if the soil is dry 2" below the surface, it's time to water deeply.
Best wishes with your new plants.
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