Map of Pecan Growing Areas

The native range of pecan occupies a wide geographical area extending from 42 degrees N latitude at the northern end of its range southward to 16 degrees N latitude. This extensive host range exposes the pecan to a wide variety of climatic conditions throughout the temperate growing regions of the planet. Pecans are grown commercially in several countries, including the United States, Mexico, South Africa, Australia, Argentina, Brazil, Peru, Uruguay, and China in both the Northern and Southern Hemispheres of the globe from about 25 to 40 degrees latitude.

Major areas of production include Georgia, New Mexico, Texas, Arizona, and Oklahoma within the U.S., the states of Coahuila, Chihuahua, and Sonora, in Mexico, as well as the Vaalharts and lower Orange River regions of the Northern Cape province in South Africa.

Major production areas have a frost-free period of 180-200 days or more. At the Northern end of the pecan’s range, certain cultivars can produce fruit with as little as 140 frost-free days.

Though they evolved within a relatively humid subtropical region, pecans are grown commercially in arid, semi-arid, and humid conditions. Within the United States, the dividing line between arid and semi-arid/humid growing conditions occurs along the 100th meridian which runs north and south through the panhandle of Oklahoma and central Texas. West of this line pecan production is entirely dependent upon irrigation to produce the crop. In this region, pecan scab disease is not a serious production problem but water supply, water quality, and soil salinity are critical issues. East of the 100th meridian, rainfall can meet a portion of the crop’s water demand but because rainfall is not always distributed uniformly in time and space, irrigation is required for consistent production and nut quality. Here, the more frequent occurrence of rainfall and humidity drives pecan scab disease development, making this the most important production constraint under humid growing conditions.