
Happy 246th Birthday, America! As this great country celebrates its independence, many turf managers in the southeast and central US are experiencingextreme heat and drought. For this article, I dug into our archives to pull together the top tips and tricks for maintaining quality, healthy turf during these challenging times.
Heat and Drought Stress
Drought and high ET (evapotranspiration ) rates remove moisture from the soil andthe plant. The net result is a stressed plant with a vulnerable root system. Ultimately, this puts the plant at risk, as it struggles to stay alive under low mowing heights and increased demand for playability. At the same time, depending on your location, salt content may build up causing further risk to the turf and the health of the soil environment.
Strategies and Tips for Turf Management Under Heat and Drought Stress
The key is to maintain a balance of enough moisture in the soil profile, keeping the turf healthy without creating wet or waterlogged conditions. Here are some strategies and tips that can help:
- Spike your Harrell'sHydroMAX® Fleet® 100 applications with a little Symphony® (water retainer) from the same line. Irrigate as usual.
- In monthly apps, apply 3 oz/1,000 sq. ft. of Fleet plus 2 oz of Symphony®
- In biweekly apps, apply 1.5 oz/1,000 sq. ft. of Fleet plus 1 oz of Symphony®
- Apply Symphony® at 1 oz/1,000 sq. ft. with your foliar apps and irrigate as usual. Then, flush salt build-up once a month with Fleet® 100 at 5-6 oz/1,000 sq. ft., Harrell'sBio-MAX® EarthMAX® Organic at 4 oz, and Harrell'sMAX® Salt Rx at 2-4 oz/1,000 sq. ft.
- Add Harrell'sBio-MAX® 4-0-0 and EarthMAX® Organic (both at 2-3 oz/1,000 sq. ft. every 14 days or 4-6 oz/month) to foliar or wetting agent applications. Both 4-0-0 and EarthMAX® Organic provide excellent drought resistance.
- If applying wetting agents monthly, use Harrell'sHydroMAX® Hydro-Cure at 2-4 oz/1,000 sq. ft. every two weeks to alleviate LDS, if necessary. Hydro-Cure is particularly helpful on collars or when a slope or a difference in soil structure creates the green droughty area.
- Use wetting agent pellets like Harrell’sHydroMAX® RootMAX and Hydro-Cure® when hand-watering and to alleviate isolated dry spots. If you have increased salt content, utilize the Harrell’sHydroMAX® CP pellets. For those with wet wells for irrigation, utilize the Harrell'sHydroMAX® SuperMAX Pellet during irrigation cycles.
- For tees and fairways, apply Harrell'sHydroMAX® Hydro-90. Hydro-90 is a unique combination of a penetrant and a retainer.
- Apply 4 oz sq. ft. every three weeks or 6 oz/1,000 sq. ft. monthly.
- Apply 8-9 oz/1,000 sq. ft. for two months of control.
- Apply split apps of 8+8 for three-four months of control.

- One more strategy that will help—instead of irrigating greens last at night, irrigate them first. At the end of the day when the turf needs the water the most, especially now with longer daylight hours, these schedule changes may be beneficial. You can also split your greens irrigation into two cycles—one at the end of the day to alleviate stress and one last in your nightly cycle to get them ready to face the next day.
Reach Out to Your Harrell’s Rep!
Please view the Harrell’s website, Harrell'sHyroMAX® catalog, for product specifics and technical information. Also, please contact your local Harrell’s sales representative for any questions you may have or for assistance in building a plan specific to your turf. Good luck and stay cool!