By Ross Greene, UGA Extension Agriculture and Natural Resources Agent, Candler and Evans Counties, Wesley M. Porter, Extension Precision Ag and Irrigation Specialist, and Sarah Beth Thompson
Editor’s Note: This article updates a July 2025 blog post, “Don’t Let Peanuts Get Dry in July” and a UGA Extension resource, “Mid-Season Irrigation Tips for July Peanuts, with current recommendations and observations for the 2026 peanut growing season.
This season has been especially tough. We went from extreme drought conditions to excessive rainfall for a couple of weeks during mid-June back to extreme heat around the 4th of July. The good news is that overall, we should have developed a thorough rooting structure in most cases due to the dry conditions during May. Now that we have moved into early July, peanuts that were planted during early May are around 60 days after planting (DAP) and peanuts that were planted in late May are at 30 DAP.
As Georgia’s peanut crop enters its period of peak water demand, irrigation management becomes one of the most important factors influencing yield potential. Peanuts planted in early to mid-May are now reaching the stage where daily water use is at or near its seasonal maximum. During this critical period, the crop may require up to 0.3 inches of water per day, making it essential for producers to stay ahead of irrigation demands rather than trying to catch up after moisture stress occurs. To help simplify this we’re looking at needing about an inch of water every three days.
While scattered rainfall has provided temporary relief across portions of the state, many producers continue to report limited subsoil moisture reserves. In many cases, rainfall has been enough to wet the soil surface but has not fully replenished moisture deeper in the soil profile. As a result, irrigation systems may need to supply nearly all of the crop’s water requirements during periods of hot, dry weather, making careful irrigation scheduling essential to maintaining yield potential.
Example: Peanuts planted on May 10 are approximately 66 days old by mid-July. According to the UGA Peanut Irrigation Checkbook, these fields are now in the middle of their peak water demand period, with crop water use exceeding 1.5 inches per week, or roughly 0.21 to 0.23 inches per day. As the crop moves further into peak water demand, daily crop water use may approach 0.30 inches per day under hot, sunny, and windy conditions.
Why Peak Water Demand Matters
Peanuts generally reach peak water usage around 55 days after planting and continue to require high levels of water until approximately 95 to 100 days after planting. After this point, crop water demand begins to decline. This sustained period of high water usage is critical for proper pod development, pod fill, and ultimately maximizing yield potential.
Peak water demand becomes even more challenging when soil moisture reserves are limited. During years when the soil profile is fully recharged, stored moisture helps buffer the crop between irrigation events. However, when deeper soil moisture is lacking, irrigation systems must replace nearly all of the water used by the crop each day. This leaves little room for missed irrigation cycles or extended periods of hot, dry weather.
In the sandy Coastal Plain soils common across much of Georgia, total available plant water is limited. For example, most Sandy Loam soils have a soil water holding capacity of 1.0 inch/ft of soil depth, and approximately 50% of this is plant available. Thus, even with an effective rooting depth of two feet, only about one inch of water is readily available for plant use. At a daily water use rate approaching 0.3 inches, that reserve can be depleted in as little as three days.
Getting behind on irrigation during this critical period can lead to irreversible yield loss. Waiting until peanuts begin showing visible drought stress often means yield potential has already been reduced. And if you wait until you see visible stress and we do not have rainfall to supplement water requirements, it is very unlikely that you will refill the profile with irrigation alone. Maintaining adequate soil moisture throughout pod development is far more effective than trying to replace several days of crop water use after stress has occurred.
During periods of peak water demand, it is also important to consider irrigation system efficiency. If the crop is using approximately 0.30 inches of water per day and an irrigation system is operating at 85% application efficiency, approximately 0.35 inches of irrigation water must be applied each day to replace the water lost by the crop. We are not suggesting that you irrigate every day, just consider the efficiency when you trigger an irrigation application.
Over the course of a week, this amounts to nearly 2.5 inches of irrigation water in the absence of effective rainfall. This example highlights how quickly irrigation demands can accumulate during July and why producers should stay ahead of the crop’s water needs rather than waiting until moisture stress becomes visible.
Tools and Resources to Assist with Irrigation Scheduling
The University of Georgia Extension Checkbook Method (https://fieldreport.caes.uga.edu/publications/C1189/irrigation-reference-guide-for-corn-cotton-peanuts-and-soybeans/) remains one of the most reliable guides for irrigation scheduling. This method combines historical evapotranspiration (ET) data with crop coefficients to estimate crop water requirements throughout the growing season and provides an excellent foundation for irrigation scheduling.
The UGA Weather Network (https://www.georgiaweather.net/) is another valuable resource. By selecting a nearby weather station and viewing the Water Balance tab, producers can estimate daily water loss through reference evapotranspiration (ET). Reference ET represents the atmospheric demand for water based on weather conditions and is not the same as actual peanut water use.
To estimate crop water use, the reference ET value must be multiplied by the appropriate crop coefficient (Kc), which changes throughout the growing season. During peak water demand, this adjustment often results in peanut water use approaching 0.20 to 0.30 inches per day, depending on crop stage and weather conditions. As temperatures increase and conditions become hotter, drier, and windier, both evapotranspiration and crop water use increase, making timely irrigation even more important.
Producers should also remember that small rainfall events do not always eliminate the need for irrigation. A brief thunderstorm may temporarily reduce irrigation requirements, but under periods of high evapotranspiration and peak crop water use, that moisture can be depleted rapidly. Continue monitoring weather conditions, crop water use, and soil moisture rather than relying solely on rainfall totals when making irrigation decisions.
Computer-based irrigation scheduling tools such as Irrigator Pro (https://irrigatorpro.org/) provide another level of decision support. These systems utilize real-time soil temperature and soil moisture data to recommend irrigation timing. Irrigator Pro can also notify producers when soil temperatures reach levels where irrigation may be recommended for cooling purposes, even when adequate soil moisture is present.
Every irrigation system has limitations. Larger center pivots or systems with lower application capacities may not be able to replace peak crop water use in a single rotation, particularly during extended periods of high evaporative demand. Beginning irrigation before significant soil moisture deficits develop gives producers a better opportunity to keep pace with crop water demand throughout July.
The UGA Peanut Irrigation Checkbook, UGA Weather Network, Irrigator Pro, and soil moisture sensors each provide valuable information for irrigation scheduling. While each tool has its strengths, the best irrigation decisions combine multiple sources of information with routine field observations and knowledge of individual field conditions.
Conclusion
Peak water demand represents one of the most critical periods of the peanut growing season because crop water use reaches its seasonal maximum during blooming, pegging, and pod development. Consistent soil moisture during this stage is essential for maximizing yield potential. By combining the UGA Peanut Irrigation Checkbook, the UGA Weather Network, soil moisture sensors, Irrigator Pro, and regular field scouting, producers can make timely, informed irrigation decisions that improve water use efficiency and help protect yield potential throughout the remainder of the growing season.
Irrigation is only one component of successful peanut production. As you manage irrigation throughout July, continue scouting fields for foliar diseases, insects, nutrient deficiencies, and weed escapes. Healthy plants are better able to utilize available water efficiently and maximize pod development during this critical stage of growth.
For more information on peanut irrigation or assistance with irrigation scheduling, contact your local University of Georgia Extension office.
Additional crop water use recommendations are available in UGA Extension Publication C 1189, Irrigation Reference Guide for Corn, Cotton, Peanuts, and Soybeans.
Acknowledgment
This article was adapted and updated from the 2025 University of Georgia Cooperative Extension Resource, Mid-Season Irrigation Tips for July Peanuts, originally authored by Jason Mallard, David Hall, Phillip Edwards, Wesley Porter, and Ross Greene. Portions of the original publication have been revised and expanded to reflect current field conditions and irrigation considerations for the 2026 growing season.