How does Janie's journey from west Florida to Eatonville to the everglades represent her and the novel's increasing immersion in black culture?
Janie's journey is one of both self-actualization and personal and spiritual fulfillment. I'm not so sure her journey is one of increasing immersion in black culture as it is one of broadening one's horizons and open-mindedness.
Certainly, as Janie moves from the white plantation, to her grandmother's house, to Logan's farm, and to Eatonville with Joe Starks, she is being immersed more and more in black culture. As we learn in Chapter 2, the first many years of Janie's life she never even realized she was black; she simply assumed she was white like all the other children on the plantation. By the time she reaches Eatonville, the all-black town, and runs the store, the "heart of it all" she is full immersed in black culture.
Her journey with Tea Cake down into the Everglades, however, represents something different. The society there is much more diverse and multi-ethnic. From the Haitians, to the Seminole, to the Bahaman dancers, to the white land-owners, to the racist African Americans such as Mrs. Turner, Janie encounters individuals and perspectives that are far more broad and diverse.
Because of this journey, Janie grows to understand herself. As she says to Pheoby near the end of the novel: "you got tuh gothere tuh know there."
Janie does immerse herself in black culture in the course of the novel but her journey is much more complex than just that. It is a quest for a kind of global perspective and understanding; as the last three sentences of the novel tell us:
She pulled in her horizon like a great fish-net. Pulled it from around the waits of the world and draped it over her shoulder. So much of life in its meshes! She called in her soul to see.
In west Florida, Janie was poor and black. This was the norm for African Americans at the time. In Eatonville, however, she is part of a group of African Americans who work to build a community that is of the Black people and for the Black people. This foreshadows much of the theme of literature written during the Black Arts Movement in the late 1950s and 1960s which focused on the revolutionary nature of Black writing and the fact that it should be collective (of the people) committed (to the growth of the people) and functioning (inspiring growth of the Black people). In a very real way, Hurston anticipated the direction of Black literature with her work.
Returning to Janie, in Eatonville she helped to build Black culture and identity, but she lost a part of herself in the process as she went from being a part of the growth to being just the mayor's wife. After his death, when she meets Tea Cake, their journey to the Everglades represented a return to a lower level of economic prosperity but to a stronger sense of both individual identity and community identity as the people she was working side by side with on a daily basis once again cared about their community more than about their own motives. In Eatonville, gossip and jealousy had become the norm, as is the case in most urbanized cultures. In the Everglades, work was hard, conditions were rough, but self-reliance went hand in hand with a group culture.
Surviving the orderal that she survived is what allowed Janie to emerge strong enough to return to the culture that had developed in Eatonville, but to return with the fortitude to rise above it.