Maintaining an optimal root-to-shoot ratio is critical. Following the traditional rule, mowing should be frequent enough so that no more than one-third of the top growth is removed at any one time. Removing more than 40% of the leaf area inhibits root growth because the grass will use more energy to regenerate new shoots than for sustaining roots. Published recommended mowing frequency during active growth based on various mowing heights is shown in the table below (republished with permission from Environmental Best Management Practices for Virginia’s Golf Courses, Table 7-3, p. 93):
Mowing Frequency Based on Various Mowing Heights
| Mowing height (in inches) |
1/3 rule height (in inches) |
Frequency |
|---|---|---|
| 0.12 | 0.18 | Every 1 – 1.5 days |
| 0.25 | 0.37 | Every 2 days |
| 0.5 | 0.75 | Every 2 – 3 days |
| 1.00 | 1.50 | Every 3 – 4 days |
| 1.50 | 2.25 | Every 4 – 5 days |
| 2.00 | 3.00 | Every 5 – 6 days |
| 3.00 | 4.50 | Every 6 – 7 days |
| 4.00 | 6.00 | Every 7 – 8 days |
In addition to maintaining an optimal root-to-shoot ratio, mowing should only be performed when field and growing conditions are good. Turfgrass stressed by excessive heat, cold, or moisture or by drought, traffic, or damage from cultural practices should be mowed at a reduced interval or not mowed at all to aid recovery. When favorable conditions return and if the turf is excessively tall, scalping can be avoided by lowering HOC in small increments so as not to remove more than 30% to 40% of the leaf blade when mowing.
Best Management Practices
- Mowing frequency should increase during periods of rapid growth and decrease during dry, stressful periods.
- Reduce mowing frequency under stressful conditions (heat, heavy traffic, drought, etc.) whenever possible.
Next: Mowing Patterns
