In The Good Earth, Wang Lung does decide to move his family south when a drought takes over the land, but this happens earlier in the novel.  In Chapter 29, Wang Lung and his family have already returned to their land, and they have met prosperous harvests over the years.  Wang Lung has taken Lotus as his second wife, and his sons are older--the eldest married and his wife is soon expecting a child.  Wang Lung buys the House of Hwang and decides to move his family from the farm to the courts at the big house.  The women continually fight, and Wang Lung wants peace, so he figures that moving them to separate courts in the House will be a good decision.