Should I water my Chinese Jade plants more?

I have taken on the responsibility of watering the plants around my duplex. There are many Chinese Jade planted along the pathways outside. They are large and usually flower every year. I’ve noticed that some of the Chinese Jade that are planted in shadier areas have very dark green leaves. The ones that are planted in areas with direct sunlight are light green with red edges. My landlord tells me they are not receiving enough water and that is why the leaves are tipped with red. He insists that the plants be watered once a week by filling the planting beds with water and letting the water soak into the soil. I do so once a week, but due to his insistance that they are not getting enough water (e.g., red leaf tips), I have been watering twice a week. I have noticed no change in the leaf color. At times, large branches have broken off at the base of the plants. My landlord speculates that this is due to underwatering as well. My question is…are the red tips an indication of underwatering or some other mis-care? And are the plants receiving too much water and that is why the branches are breaking off at the base of the plants. Thanks so much!