Turfgrass plants need water to survive.  Plants access moisture through precipitation, irrigation, and capillary flow.  Plants lose moisture through evaporation, transpiration, and drainage.  To aid precipitation and capillary flow, and make up for what is lost to evaporation, transpiration, and drainage, water is supplied to turfgrass areas via irrigation.  Irrigation is important for healthy turfgrass growth due to the following reasons:

- Supplies moisture for turfgrass growth
- Helps maintain turf’s green color

- Necessary for photosynthesis
- Modifies turfgrass tissue temperatures on hot days
- Aids plant rigidity
- Decreases weed encroachment
- Improves tolerance to insect and disease pressure
- Washes in fertilizers and some pesticides following application
- Maintains sufficient surface moisture to promote germination of turfgrass seed
- Reduces surface hardness
- Reduces dust and improves traction on baseball and softball infields

Turfgrass should be watered on an as needed basis. Effective irrigation applies enough water to soak the rootzone but avoids loss to drainage or runoff.  In general, turfgrasses require 1-1.5 inches of water per week, minus any rainfall, during their active growing period to remain healthy and resilient.  Soil texture, compaction issues, rootzone depth, and infiltration capacity all influence the frequency of irrigation events and the amount of water that is applied.  For more information on turfgrass soils and drainage, click here.  Other special considerations, such as weather and climatic conditions, timing, and soil moisture tools, will assist in the planning of irrigation events.

Additional Irrigation Resources:

STMA Technical Bulletins:
Effective Water Use 
Field Management During a Drought 
Conducting an Irrigation Audit 
Water Conservation Best Management Practices for Sports Facilities 
Heat and Drought Stress Effects on Sports Field Management 
Water Tables 
Water Availability 
Amount and Frequency for Irrigation Application 

United States Drought Monitor
Irrigation Association of America 
Sports Field System Design - Hunter Industries
Purple Gold: A Contemporary View of Recycled Water Irrigation

University Resources by Region:
     Basics of Evaporation and Evapotranspiration - University of Arizona
     Interpreting Irrigation Water Test Results - University of California

Mid Atlantic:
     Sports Field Irrigation - University of Kentucky
     Irrigation - University of Tennessee

     Water Conservation and Use-Efficiency - University of Georgia
     Tools for Turfgrass Irrigation Water Management - North Carolina State University
     Irrigation Water Quality Problems - Dealing with a Management Challenge - North Carolina State University
     Water Management on Turfgrasses - Texas A&M University

     Tips for Athletic Field Seeding and Irrigation - Iowa State University
     Smart Irrigation Technology: Controllers and Sensors - Oklahoma State University

     Maximizing Irrigation Efficiency and Water Conservation - University of Massachusetts
     Turf Irrigation and Water Conservation - University of Massachusetts
     Turfgrass Response to Water Deficits - University of Massachusetts
     Management Tips to Improve Turfgrass Drought Survival - University of Massachusetts
     Irrigation Water Quality Guidelines for Turfgrass Sites - Penn State University
     Principles of Turfgrass Irrigation - Penn State University
     Watering - Cornell University

Webinars and Podcasts:
Smart Irrigation Practices - Webinar presented by Dr. Alec Kowalewski
Ohio State University Podcast - Irrigation
Ohio State University Podcast - Salt Affected Turfgrass Sites 

Irrigation Sessions Featured at STMA Conferences:
2015 - Improving Water Efficiency: Take the Million Gallon Challenge! - Brad Jakubowski
2015 - Using Soil Moisture Meters to Make More Informed Irrigation Decisions - Shane Conroy
2015 - ET, Irrigation Efficiency, Water Management, and Conservation - Brent Mecham
2014 - Using Soil Moisture & Temperature Sensors as a Part of an Integrated Approach to Managing Athletic Fields – Amy Fouty, CSFM
2014 - Understanding the Basics of Irrigation Design, Installation, and Troubleshooting – Lynda Wightman
2013 - STMA 106 - Subsurface Drip Irrigation for Sports Turf Speaker: Bernd Leinauer, Ph.D. 
2013 - STMA 309 - Optimizing Sprinkler Uniformity with an Irrigation Audit; Irrigation Formula Handout Speaker: Jeff Gilbert
2012 - Irrigation Water Quality Evaluation and Management
Speaker: Dr. Ali Harvandi, University of California
2012 - Managing Turfgrasses During Drought
Speaker: Dr. Ali Harivandi, University of California
2011 - Irrigating Turf with Effluent/Salt Water (also available as a recorded session here)
Jim McAfee, Ph.D.
2011 - Water Reduction 101 - An Audit Competition (also available as a recorded session here)
Speakers: Michael Carr, Gordon Kunkle

International Resources