Rainwater was channeled from the desert hills and peaks onto dryland farms where  teparies and other crops such as squash and corn were grown. These crops were adapted to growing and producing a crop which was essentially irrigated once from the winter rains or summer storms. In some areas of Arizona, these channels on the hills and peaks are still visible although the dryland farm has returned to the desert.

Planted in April and harvested in August, these are the only beans that are adapted to the extreme summer temperatures of South and Central Arizona. Fast growing and early maturing, these beans are well adapted to the limited water supply of Central and Southern Arizona. Early spring, after the danger of frost, is the best time to plant tepary beans in the field.

This is especially beneficial if the crop is irrigated only with the runoff rainwater from the winter as they were originally farmed by the native people of Arizona. Roots grow fast and deep to utilize the soil moisture. The crop flowers and matures early before the soil water is depleted. Extreme temperatures of June and July do not interfere with pollination and bean pod production as is the case with common beans.

Water is a limiting factor for this crop. Too much water will produce an excess of vegetation which can be used as a forage crop but a very small amount of beans. The beans can produce a decent crop with as little as three irrigations. Production up to 2000 pounds of beans per acre can be obtained when the plants are not stressed for water. This crop in 2004 required about 48 inches of applied water to produce 2000 pounds of beans per acre.

Studies by the University of Arizona in 1911 show bean yields of spring planted tepary beans of 2000 and up to 3000 pounds per acre on irrigated farmland in the Yuma valley. Dryland farming of tepary beans in McNeil, Arizona (1909 and 1910) would produce 300 to 500 pounds of beans per acre. Supplemental irrigation of about 4 acre-inches of water would boost production to 750 pounds of beans per acre. Unfortunately, there is no documentation of the actual amount of rainwater or total irrigation water applied during these early agricultural trials.