Wheat

The cultivation of wheat has been a primary activity in South Australian agriculture since European settlement in 1836. During the 19th century wheat and wool were almost the only South Australian products that could absorb the high cost of transport to outside markets and remain profitable.

From 1836, European settlement in South Australia was mainly on land close Adelaide - in areas, such as the Mount Lofty Ranges, which appeared to the settlers to have reliable rainfall. As more land was surveyed and that which was already settled was more intensely cultivated farmers moved to other areas of the colony. Wheat was found to be a crop suited to the South Australian climate; the hot and dry summers inhibit the stem rust which can blight crops in wetter climes. In the early 1850s, the Victorian gold rush and the development of paddle-steamers on the River Murray as a means of transporting goods to the eastern colonies saw a boom in the demand and an opening of new markets for South Australian wheat. In 1865 there were 76 flourmills in South Australia, most run by steam engines. Between 1865 and 1890, half of the land on which wheat was grown in Australia was in South Australia.

In 1869, the South Australian government passed the Waste Lands Amendment Act (known as the Strangways Act) which allowed farmers to buy greater areas of Crown land per section than the previously granted and to purchase on credit. This further added to the push to settle previously uncultivated land, including into the colony's dry interior.

In 1865, South Australia's surveyor-general, George Woodroffe Goyder, had surveyed the northern areas to determine which land received enough rainfall annually to support agriculture. The result was Goyder's Line of rainfall; the area north of the Line could not sustain farming. Initially, the government would not sell Crown land north of the Goyder's Line to farmers. However, developing from the provisions of the Strangways Act, in 1874 the government allowed for the disposal of any public land south of the Northern Territory border. This, in combination with a series of wet years in the 1870s, saw some optimistic farmers ignore Goyder's Line and establish farms to its north. Many were to be ruined in the following decade when a succession of dry seasons devastated their crops. More successful were those who took up land on Yorke Peninsula, still a wheat growing area today, although barley is now the mainstay crop.

After a period of stagnation in the 1880s and '90s when drought, soil exhaustion and disease decreased wheat crops, South Australian wheat farmers were assisted in the early 20th century by superphosphate fertilisers which increased the fertility of heavily cultivated land. Newly developed fertilisers also assisted in preparing the sandy soils of the Murray Mallee and the north of the Eyre Peninsula for wheat-growing.

Some notable South Australian inventions have greatly assisted the wheat farmer. Flour miller John Ridley's stripper harvester mechanised the reaping of wheat in 1843; in the 1870s Charles Mullen developed a process by which land was cleared of mallee stumps, known after him as Mullenising; and the Smith brothers of Yorke Peninsula invented the stump jump plough in the late 1870s - a plough that 'jumped' over tree roots and stumps negating the labour intensive task of clearing them from the land before cultivation could begin.