Understanding Grass Needs
Cool- and warm-season grasses respond differently when water is limited. In general, cool-season grasses lose more water through their pores and are less efficient than warm-season grasses in managing water under stress. For example, some Kentucky bluegrasses can use 50% more water per day than Bermudagrass. In some circumstances, the difference may be even greater.2
In addition to differing water usage, lawn grasses vary in drought resistance and drought tolerance. Some grasses avoid drought by retaining more water or growing deeper root systems, others escape drought by going dormant, and still other types resist drought effects by tolerating dehydration well. Growing regionally appropriate grasses increases your lawn's potential to conserve water and retain health and beauty when water is limited.
Growing water-conserving grass varieties, such as those qualified by the Turfgrass Water Conservation Alliance® (TWCA), translates to lower water usage, less lawn maintenance and more time to enjoy your lawn. Whether cool- or warm-season grasses, TWCA-qualified varieties have undergone rigorous testing to prove statistically significant drought tolerance over similar grass species.3 Pennington® Smart Seed® grasses, for example, require up to 30% less water year after year than ordinary grasses, and they stay green for up to three weeks without water.
Watering Wisely Under Normal Conditions
Implementing these water-wise watering practices, as part of your regular lawn maintenance routine keeps lawns healthy while cutting down on wasted water:
- Use rain gauges or weather data to track how much weekly water nature provides, then supplement only as needed. Too much water prevents roots from getting needed oxygen and encourages many types of lawn disease.
- Monitor how much water your sprinkler system provides; don't guess. Set up water gauges or 1-inch-deep cans (tuna cans or cat food cans work well). Measure the sprinkler water you collect in 15 minutes to determine how long it takes to supply 1 inch.
- Water your lawn between 4 a.m. and 10 a.m., whenever possible. Early morning watering reduces loss to wind and evaporation, and allows water to soak in before sunlight heats the soil.
- Use watering systems that stay close to the ground. Arcing sprinklers waste more water than systems with low trajectories.
- Water ordinary grasses deeply once or twice per week, if needed. Shallow, frequent watering leads to shallow, drought-vulnerable roots. Deep, less frequent watering encourages deep roots and improves drought tolerance.
- Distribute water evenly and slowly to prevent puddling or runoff, and avoid watering sidewalks or other paved areas. Consider intermittent sprinklers that water briefly, then allow a soak-in period before continuing.
Responding to Drought and Water Restrictions
- Reduce irrigation gradually over several weeks, instead of all at once. This allows grasses and other landscape plants to acclimate to water shortages.
- Adjust watering or irrigation schedules every week to compensate for current weather conditions and changing regulations.
- Adjust irrigation systems to reduce or avoid watering areas that receive shade, and keep available water focused on exposed lawn.
- Consider smart controllers, which sense soil moisture and automatically adjust irrigation based on current soil and weather conditions, to minimize water use.
- Shut down automated irrigation systems during severe shortages, and water critical areas by hand only.
- Avoid fertilizing. Fertilizer promotes new growth that requires more water, and stressed lawns are also more prone to fertilizer burn.
Using the Pennington Seed Water Calculator
By using current statistics for your location's real-time weather and its rates of evaporation from land and transpiration (or evaporation) from plants — collectively known as evapotranspiration rates — this interactive tool provides guidance whether you're watering for premium greenery or survival mode. Just plug in a few facts about your grass, goals and watering system, and let the calculator do the rest. Pennington Seed is dedicated to helping you grow the lushest, healthiest, water-conserving lawn possible.
Turfgrass Water Conservation Alliance is a registered trademark of Nexgen Turf Research, LLC. Pennington and Smart Seed are registered trademarks of Pennington Seed, Inc.
1. U.S. Environmental Protection Agency; “Outdoor Water Use in the United States"
2. University of California Division of Agriculture and Natural Resources, “Managing Turfgrasses During Drought," August 2009.
3. Turfgrass Water Conservation Alliance, “Protocols"
4. The Lawn Institute; “Watering Basics for Established Lawns"
5. The National Drought Mitigation Center, “Drought Condition (Percent Area): United States," September 2015