Peaches are among the most popular fruit trees for backyard gardeners, especially in the southeastern U.S. And, now that the summer is upon us, a common question from backyard gardeners is: when and how much should I irrigate my peach trees?
Water is critical for optimal tree growth and fruit development. South Carolina has a humid subtropical climate that provides water throughout the growing season. However, water demands are high, especially for mature trees at certain times of the year, and can significantly reduce yield and fruit quality. Specifically, peaches are very sensitive to insufficient water three weeks before harvest. During this period, a fully-grown, mature peach tree may require up to 35-45 gallons of water per day. NOTE: one- to two-year-old trees do not typically require irrigation unless there is a drought.
Monitoring rainfall and soil moisture can be helpful to understand how much water is needed. On average, 1 and 1.5 inches of water per week will provide sufficient water for a mature tree. If there is not enough rainfall, supplemental irrigation is needed; consider watering them deeply, two or three times per week. Spreading mulch around the tree in a depth of 2-4 inches will help to conserve soil moisture. Avoid piling the mulch against the trunk and also avoid forming mulch volcanoes. For more information on mulch, see HGIC 1604, Mulch. Mid-summer and postharvest drought periods can also affect flower and fruit development the following spring, as it is during this time when next season’s flower buds start to form. “Doubling” (double peach fruits in early spring) is a consequence of drought stress during the previous season. Thus, irrigation may be needed at after harvesting if there is a persistent drought.
For information on variety selection, fertilization, pruning, thinning, and pest and disease control, see HGIC 1354, Peaches and Nectarines; HGIC 1355, Pruning Peaches and Nectarines; and HGIC 2209, Peach Diseases.