The early Maryborough economy was centered around livestock farming, logging of the bunya pine forests, and the boiling down of animal carcasses to make tallow. In the late 1850s the soil along the Mary River was deemed ideal for the cultivation of sugarcane and in 1859 Edgar Thomas Aldridge was able to grow and produce a world-class experimental crop. Seeing the profitable potential, many influential local landholders such as Henry Palmer and John Eaton formed the Maryborough Sugar Company in 1865. Farmers switched to growing cane and the first Mary River sugar refinery, known as the Central Mill, was built in 1867 by Robert Greathead and Frederick Gladwell.
At this time, other sugar plantations in Queensland were importing cheap, sometimes black birded labor from islands in the South Pacific. The planters along the Mary River also used this type of labor and the first shipment of 84 South Sea Islander workers arrived in Maryborough in November 1867. They came aboard the schooner Mary Smith, owned by Robert Greathead, with 22 of the laborers being engaged by the Maryborough Sugar Company. Concerns were raised about whether the Islanders on the Mary Smith understood the work contracts and if the pledge to return them would be honored due to the lack of an interpreter. It was also alleged that the captain sold the Islanders to the colonists for £9 a head, while a missionary noted that the Islanders were unlikely to understand why they were taken.
In 1869, Robert Tooth and Robert Cran bought up a number of plantations in the region and established the Yengarie Sugar Refinery. They became the local dominant sugar manufacturer with the Maryborough Sugar Company becoming insolvent. By the end of the 1870s, Robert Cran and his sons had taken control of operations under the name Cran & Co.