The two purchased 561 acres (227 ha) of land on the island of Maui between Pāʻia and Makawao, on which they began to cultivate sugarcane.

The land the partners cultivated was semi-arid former dry forest, not ideal for growing sugarcane, a crop that required much water.

Samuel Alexander realized that rain was plentiful miles away in the rainforests on the windward slopes of Haleakalā mountain.

Following World War II, the company entered a new business: land development and real estate.

In addition, Alexander & Baldwin entered diversified agriculture, beginning to cultivate coffee and macadamia nuts in the 1980s.

"[11] Maui environmentalists and physicians countered by asserting that the burning process caused increased rates of asthma and respiratory disease, especially among children, released carcinogens from burning PVC pipes used in the irrigation system,[10] and resulted in highway closures and car crashes.

[15] The company's Puunene Mill had also attracted criticism from residents, who pointed out that its equipment did not meet federal emissions standards and that its high coal consumption produced unsafe levels of sulfur dioxide.

[16] Some activists had reported receiving threats from or being assaulted by HC&S employees and members of the International Longshore and Warehouse Union, which had been active in lobbying for continued cane burning on behalf of Alexander & Baldwin.

[10][13] The company's agricultural practices, as well as its history and the careers of its missionary founders, were satirized by Maui author Tim Parise in the novel Totum Hominem.