The main seed crops produced by the New Zealand arable industry in the early 2000s are:
- cereals, such as wheat, oats, barley and maize
- pulses, such as peas and lentils
- brassicas, such as oil-seed rape (also known as canola)
- herbage, forage and vegetable crops, such as ryegrass and white clover, which are grown as annual crops to harvest the seed.
The grain harvested from seed crops has many uses, including milling, malting, manufacturing animal feed and pressing for oil. Milling involves crushing the grain and separating the tough outer husk from the flour. Malting is a process where the grain, usually barley, is germinated, then heated and crushed, before being fermented and made into products such as beer or vinegar.
Some arable crops are grown as forage for grazing animals rather than for grain. These include cereals such as oats and maize, and brassicas like swedes, turnips, rape and kale.
Other arable crops, such as potatoes, carrots and broccoli, are grown as vegetables for human consumption.
In the past, arable crops like sugar beet have been used as biofuels. This application may become more important in the future, with renewed interest in alternative fuels.
In 2002, 42,000 hectares of wheat, 78,000 hectares of barley, 14,200 hectares of maize, 7,400 hectares of oats and 10,900 hectares of peas were grown in New Zealand. There were also 20,000 hectares of pasture seeds and about 10,000 hectares of other crops, mainly vegetable and brassica seeds.
Of the 301,500 tonnes of wheat produced, 46% was used for milling. Total barley production was 441,000 tonnes, with 35,000 tonnes of oats, 149,000 tonnes of maize and 30,000 tonnes of peas.
In 2002, 68% of New Zealand’s arable production land area was in Canterbury, which yielded 90% of the milling wheat and 80% of wheat used as feed. Other wheat-growing regions were Southland, Otago and Manawatū–Wanganui.
Canterbury produced 68% of New Zealand’s barley, but significant volumes were also grown in Southland (10%) and Otago (10%), and also in the Wairarapa and Manawatū.
Oats were grown in Canterbury (60%), Southland (24%) and Otago (9%).
Peas were produced mainly in Canterbury (76%), with smaller volumes coming from Hawke’s Bay, Manawatū–Wanganui, Wellington, Marlborough, Otago and Southland.
In contrast to the other crops, 97% of maize grain was grown in the North Island. Major maize-growing regions were Waikato (25%), Gisborne (19%), Manawatū–Wanganui (16%), Bay of Plenty (14%) and Hawke’s Bay (14%).