Eliza is a sixteen-year-old left in charge of her family's South Carolina plantations when her father returns to Antigua. She is an avid horticulturist who defies the gender norms of colonial America. She seeks financial independence through the difficult cultivation of indigo dye. Though capable, she struggles to manage the power imbalances of her position and her family's strict expectations.

Benoit, known as Ben, is an enslaved young man who grew up with Eliza in Antigua before being sold to an indigo maker in Montserrat. He holds extensive, generational knowledge about cultivating and extracting indigo dye. Literate and observant, he criticizes the laws keeping other enslaved individuals uneducated. He carefully guards his botanical expertise as leverage for his own future.

Charles is a wealthy, established lawyer and neighboring plantation owner in Charles Town. Considerably older than Eliza, he serves as an early advocate for her management role and offers critical legal support. He values intellect and progressive ideas. He defends Eliza's unorthodox ambitions against local critics.

Ann is Eliza's mother, a woman deeply devoted to traditional British societal norms. Prone to illness and headaches, she views her daughter's agricultural ambitions as unladylike. She arranges suitors and hopes to secure a marriage match for Eliza to ensure a return to their comfortable life in Antigua.

Sarah is an enslaved woman who possesses crucial knowledge about indigo production. Originally held at the Waccamaw plantation where she endures abuse, she is forcibly relocated to Wappoo by Eliza. This disruption sparks a deep, volatile resentment toward the young plantation manager.

Starrat is the brutal overseer at Colonel Lucas's Waccamaw property. He rules through fear and maintains a whipping post despite requests to remove it. He openly disdains taking orders from a teenage girl and attempts to physically intimidate Eliza during her visits.

Nicolas Cromwell is an indigo maker from Montserrat hired by Colonel Lucas to guide Eliza's efforts. Condescending and prone to gambling, he attempts to usurp Eliza's authority. He routinely claims credit for his apprentice's botanical knowledge while plotting to secure his own financial stability.

John Laurens is a wealthy merchant aggressively seeking to purchase plantation land in South Carolina. He views Eliza's authority with contempt and attempts to manipulate her circumstances. His callous, abusive behavior causes immediate conflict during his uninvited visit to the Wappoo plantation.

Colonel Lucas is Eliza's father, a British military officer who inherited three plantations in South Carolina. Driven by career ambitions in Antigua, he entrusts the management of his American lands to his teenage daughter. He recognizes Eliza's intelligence but often yields to social conventions regarding marriage and plantation oversight.

George is Eliza's older brother and the expected heir to their father's estate. He is largely absent as he completes his soldier's training in England.

Polly is Eliza's younger sister. Described as a chatterbox, she looks up to Eliza as a maternal figure while their mother is frequently indisposed.

Tommy is the youngest Lucas sibling, currently living abroad in England for his education.

Quash is an enslaved driver and carpenter on the Lucas family's Wappoo plantation. Quiet and capable, he protects the Lucas women during periods of local unrest. He assists Eliza in her early attempts to renovate the property and clear land for her indigo experiments.

Essie is an enslaved maid who functions as a surrogate mother figure for Eliza. She observes the household dynamics closely. She frequently offers guidance and warnings based on her spiritual beliefs, attempting to shield Eliza from unseen dangers.

Henry is John's son, a young man whom Eliza's mother views as a potential suitor. He shares his father's opportunistic views on acquiring land and exploiting indigenous populations for labor.

Elizabeth Pinckney is Charles's wife. Though dealing with poor health and the sorrow of being unable to have children, she is exceptionally kind. She openly supports Eliza's unorthodox ambitions and offers the young woman social protection in Charles Town.

Miss Bartlett is the niece of Charles and Elizabeth Pinckney. She visits her relatives in Charles Town and quickly becomes Eliza's close friend. She acts as an intermediary for correspondence between Eliza and Charles.

Mary is the daughter of the Woodward family and one of Eliza's few female friends in the area. While she supports Eliza personally, she holds conventional, prejudiced views regarding the enslavement of African people.

Mr. Deveaux is a neighboring planter and horticulturist. He encourages Eliza's early agricultural experiments. He provides her with woad indigo seeds and advice on double-watering cycles before she secures higher-quality seeds.

Togo is an enslaved worker on the Wappoo plantation. He diligently assists Eliza in the physical labor of planting and harvesting. He reports on crop progress and delivers news to the main house.