Mowing height

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Proper Mowing Equal’s Quality Turf

Mowing frequency is dictated by how fast the grass grows. In most circumstances one time per week is adequate but occasionally more frequent mowing may be necessary. Remember never to remove more than 1/3 of the grass blade at each mowing. The key here is not to fall behind on your mowing schedule.


If you didn’t scalp this spring you will have poor quality turf this year. Keep your warm season turf cut at 1 ½ ” to 2 ½ “. There are exceptions when you may be forced to mow higher or it is expedient to do so. If you have an excessively bumpy lawn and the mower is scuffing the ground then you may have to mow higher until you can level the ground. As the summer temperatures climb, mowing the turf may cause firing at the two and one-half inch height. Firing is that burned or yellowed look that can appear after mowing. This is caused by removing too much grass blade at one time and thrusting the turf into severe desiccation and water loss.  Firing is an indication you need to mow more frequently or raise the mower height.

Closely mown warm season turf requires an increased mowing schedule during periods of heavy, rapid growth if it is to be maintained at a very short height.  All warm season turfs, even reel mowed turfs, need to be allowed to start to grow out starting in August.  All warm season turfs should be at 3″ before the turf starts to go dormant in October.  The result of not allowing the root system to store carbohydrates before dormancy is a weak root system that is very susceptible to expensive fungal problems, slow green up in the spring, and even turf death.

For years, turf research has been telling us that the warm season turfs need to be allowed to recover from summer’s short mowing heights in order to build carbohydrates in the root system to survive the winter and to have sufficient energy for spring greening.

Also for years, most maintenance companies have ignored that wisdom in order to keep their maintanined lawns short (oftentimes very short) simply because their clients like the look. I like the look too, but we are experiencing far too much disease that we cannot control as a result. By allowing the turf to start growing out at the beginning of August we can achieve healthier turf as well as good looking turf, albeit longer turf. The turf will still look neat and because it is healthy going into fall, there will be fewer problems with patchiness in the spring.

Fungicides are wonderful tools to have in our arsenal but they are superficial fixes for the underlying cultural problem and cannot replace smart mowing practices. Also, although frustrating, the reality is that the fungicides do not make the lawn 100% perfect. Nothing we have will replace proper maintenance.

Change takes time but we need to change! Someone, somewhere started the practice of sever pruning on crepes every year which was widely and mistakenly adopted only to create some of the worst cases of “crepe murder” I have ever seen. That is slowly being replaced as people start planting crepes in situations where they have the room to grow with maintenance companies showing them how to prune properly.

This is just another situation where once the improved results are visible the modification to the mowing programs will happen.

To this end, I am again heavily stressing the need for all all of you with Bermuda and Zoysia, to start allowing the turf to grow out by raising the mower heights, starting August 15 each year until they effect a height of 3″ by October. This will be in the newsletter, on surveys, on my web page, and in our hand written notes. I will be hammering this home at every opportunity and wanted to be certain that you were aware of my campaign. Everyone needs to understand that we can not fix the problem with fungicide applications because that approach is rapidly becoming less effective each and every year. Fungicides, even for those willing to pay the extra cost, are not designed to fix a cultural problem and will never effectively control the problem. We need to save our fungicide use for where it will truly be effective against diseases that do not respond to changes in cultural practices or we will lose the effectiveness against all problems. This is no different than the overuse of antibiotics and we need to be proactive for the sake of our companies and the customer’s landscapes.


Do not stress the turf by cutting it too short. Maintain your cutting height at 2½” – 3″. Do not cut the turf when wet if at all possible. If you need to mow the turf when wet or if you prefer to mow without a bag (which is acceptable) then blow off the resulting clippings to prevent them from clumping up on the turf. These wads of clippings, if left to rot, can kill spots in your turf and encourage disease.

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