Pecan Tree Irrigation Needs

Pecan trees are large, deciduous, nut-producing trees. The fact that these trees are native to the Mississippi should give you a clue about their water requirements. Although pecans establish deep roots, the majority of water for nut production comes from the top two feet of the soil, which is easily accessible. Pecan trees need a lot of water. Inadequate watering will stress them. Leaves will prematurely drop and poor quality nuts will result.

When and how much water -Watering needs peak annually in the fall during nut production. Mature pecans require consistent watering, in the range of 200 gallons a day per tree. During late summer to early fall, increase this amount to at least 300 gallons per day. In particular, the first two weeks of September are considered to be the critical watering period for pecans. It is not unusual for sprinklers to run around the clock on commercial pecans farms during this time.

References:

University of Florida IFAS Extension: The Pecan Tree; P.C. Andersen and T. E. Crocker; May 2004
University of Georgia College of Agricultural & Environmental Sciences: Cultural Management of Commercial Pecan Orchards; Lenny Wells and Kerry A. Harrison; Jan. 21, 2010
How Much Water Does a Large Pecan Need for Survival?