About two million hectares (4.9 million acres), or 16% of all land, can be classified as arable. Most of the agricultural land is concentrated in the west-coast provinces of North and South P'yongan and North and South Hwanghae. Irrigation, land reclamation, and flood-control projects have been carried out, especially in rice-growing areas; about one-half of the arable land is irrigated.
Rice is the principal crop, occupying 29% of all farmland in 1999. Total rice production was put at 2,343,000 tons in 1999, compared to 5.6 million tons in 1985. Improved rice yields have been achieved through the use of "miracle" rice strains, intensive application of fertilizer, and mechanization. In 1998 there were some 75,000 tractors in use, or about one for every 27 hectares (67 acres) of cultivated land. Double-cropping of rice is not possible because of the climate, but double-cropping of other grains has been maximized through the use of cold-bed seeding and new seed varieties, so that an estimated half of all cultivated land yields two harvests. The leading grains after rice are corn, wheat, millet, and barley. Other important crops include soybeans, potatoes, sweet potatoes, pulses, oats, sorghum, rye, tobacco, and cotton. The DPRK long claimed to be self-sufficient in grain products, with total production (including rice) increasing from seven million tons in 1974 to 13.6 million tons in 1985, but falling to 4.0 million tons in 1999. Heavy rains in 1995 caused severe flooding in the DPRK, affecting over 5.2 million people and damaging crop production. Since 1996, there have been reports of widespread food shortages and famine in the DPRK.
The country's farms were collectivized after the Korean War. The movement began late in 1953, and the process was completed by August 1958, when all of the DPRK's 1,055,000 farm families had become members of over 16,000 cooperatives. In order to establish larger and more efficient operating units, the cooperatives were merged in the autumn of 1958 into approximately 3,800 units with about 300 families each. Produce is delivered to the government, which controls distribution through state stores. Most farm workers retain small private plots (less than 100 sq m/1,100 sq ft) and can sell produce from them to the state or in peasant markets.