Engagement with global trade also radically reshaped agriculture in the area around Elmina. While we have no direct records of the crops farmed in Dominase and Ponkrum at the time of their establishment, we know that engagement with the Portuguese and, later, Dutch owners of Elmina castle contributed greatly to the transformation of agriculture in this area. The Portuguese introduced a large number of crops from South America, including maize, cassava, sweet potatoes, groundnuts (peanuts), hot peppers (capsicums), and tomatoes. Other crops introduced later include bananas, oranges, sugarcane, pineapples, pawpaws, cashews, mangoes, plantains, and many species of beans. These introductions were not, by and large, imposed on the population, but rather were efforts by local farmers to take up some of the crops farmed by the Portuguese for their own needs. Cattle, sheep, pigs, and goats were also introduced to this area in the same manner. Thus, the contact with Europeans resulted in a remarkable transformation of the local agroecology, with farms throughout the region incorporating these new crops with great speed.
Such incorporation is no simple task, as the introduction of a new species to an existing ecology comes with several risks. The species may not survive because the soils, timing of seasons, weather, or pests in the area can present insurmountable barriers. The new plant might survive but cause other crops with which it is intercropped to have lower yields because of the way it uses water and/or soil nutrients or because of the pests it might attract. In some cases new species might become remarkably successful in a new setting and start to take over, choking off existing food crops and other local species. None of these outcomes appears to have occurred with plants introduced in and around Ponkrum, which speaks to the skill of local farmers in managing this process of incorporation.
Over time the introduction of new crops to the colonial holdings that would later become Ghana, including the area around Dominase and Ponkrum, became a part of official policy. The slave trade, though abolished by the British in 1807, did not wind down for a decade or two, making trade with this area less and less profitable. To earn income for their mercantile efforts, the European powers began to introduce cash crops that might be exported for profit. For example, by 1820 the British were promoting the growth of oil palm in their holdings around Cape Coast, less than ten miles to the east of Dominase and Ponkrum. While Elmina was a Dutch holding at that time, it is likely the oil palm trade reached the newly settled villages of Dominase and Ponkrum. George Mclean, the British governor at Cape Coast, pushed for the expansion of this trade, and by 1850 oil palm products were the principal items of trade in the area.
Without the slave trade, the Dutch owners of Elmina castle found their investment less and less profitable. In 1872 they transferred their West African holdings to the British, who consolidated the territory around Elmina with other territories to the north to form the Gold Coast Colony in 1901. To ensure these holdings were profitable, the British colonial government focused on the export of gold and the introduction of cash crops. Production of oil palm for export peaked in 1884, before going into a long decline due to challenges from other products in virtually every area of its utility. This instability gradually eroded oil palm's popularity as a cash crop. Although palm products accounted for about 50 percent of the total exports of British West Africa in the period up to 1900, by 1930 its export share had declined to 33 percent, and by the 1950s to 15 percent. Therefore, by the late nineteenth century the Gold Coast Colony (it would not be known as Ghana until independence in 1957) was still seeking an alternative export to replace the long-defunct slave trade.
While oil-palm exports began to decline after 1884, the meteoric rise of cocoa production in the forest areas of the Gold Coast Colony furthered this downturn after the turn of the 20th century. Cocoa production was at virtually zero in 1900, but by 1910 the colony exported nearly 40,000 tons of cocoa, and by 1921 over 130,000 tons. By the end of the 1920s cocoa accounted for 80 percent of all exports from the Gold Coast Colony. By comparison, mining of the gold from which the colony had taken its name, as well as other minerals, made up a mere 5 percent of all its exports by the late 1920s.