The old man told the house to dig a pond and plant mulberry trees behind it. What's the story?
In ancient times, people thought that water was the source of everything, and water also represented money and wealth. Therefore, water is very important in many ancient buildings. Look at the facades of some ancestral temples, which are basically pools or ponds. This is the importance people attach to water. Basically, people who have the ability will dig a pond at their doorstep. This pond is not used for raising fish, nor for beauty, but for letting their money flow into their homes like running water.
As for planting mulberry trees behind the house, mainly because? Sang? Heel? Mourning? Homophonic, so the older generation thinks that this kind of tree is unlucky in front of the house, and it is easy to bring some unnecessary trouble to the host family, so it is not planted in front of the house, but in the back. As for why it is mulberries, it is because the life in ancient China was cultivated by men and woven by women. The cloth woven by women is made of silk, and mulberry leaves happen to be silkworm's favorite food.
Therefore, this old saying, which is often talked about by old people, actually has no important significance and function now. It is purely the legacy of feudal ideology and culture. As we modern people, some old sayings have some truth, but some are unrealistic and meaningless. To distinguish between them, we can neither be completely sure nor completely negative.