The monsoons are upon us, and so is the humidity.  We need to take advantage of it and get our lawns and sod filled in while we have optimal growing weather.  

I moved away from Michigan years ago not only because it was cold, but because I hated the humidity.   I have a different appreciation for it here.  Since I am in the turf profession being uncomfortable for a couple months is not a big deal as long as it is helping our grass.  The humidity plays a couple different roles with the grass as it actually allows us to cut the watering back, and use some of what Mother Nature has provided us with–it gets those stolons moving to fill in weak areas.   We all know that rain is a blessing and we get very little of it in the desert, but a raised dew point and higher humidity means moisture stays in the plant longer.  That in turn means a little less water that needs to be applied to the grass.  I am not talking about getting carried away, but you can take a few minutes off the timer when we have these kinds of conditions and save a few gallons of water. 

Everyone that overseeds their lawn may have noticed the sudden die off of ryegrass in the last week after we had humid conditions for a week.  It only takes a few days of humidity and 110 degree heat to wipe out that stringy ryegrass.  If you have seen a black appearance to the turf in the last few days you know exactly what I am referring to.  The unfortunate part of the die off is what is left underneath.  I have been preaching to everyone to give their lawn a 100 growing days without competition, but if you are just now losing the ryegrass you are not going to be left much growing underneath.  I am going to address how to fix the weak areas and what a few magic bullets are that will get the lawn going in the right direction.  

The weak areas still need to be verticut and thinned out before you can get any recovery on your lawn.  Take a look at the picture and you will notice how much dead material is between the bermudagrass leaves and that is preventing the stolons from filling the spots in.  While that ryegrass sure filled those voids well a few weeks ago, it is not a pretty site right now.  If you don’t want to rent a verticut or just have a few small areas take a thatch rake and get all that dead, decaying material out and fill in the areas with sand.  The sand will keep the ground level when the stolons start to move across your yard. 


If you have bermudagrass, don’t be afraid of a little nitrogen right now.  An application or two of ammonium sulfate 21-0-0 at 5 pounds per 1000 SF will give your lawn a great jump start and will green it up in a hurry.  If you have a lot of growth already but still wants to feed your lawn stick with the organic fertilizers such as Milorganite, or even a balanced fertilizer such as 15-15-15, 16-20-0, 21-7-14, 6-20-20.  Do not apply any weed and feed to your lawn during this time of the year.  It is much too hot outside and you will have a significant amount of turf loss if it is applied.  If you have a paspalum lawn there is no need to put anything down with nitrogen at this time of the year.  If you are looking for a little color stick with the micronutrients and trace elements such as Manganese, zinc, and iron.


Maintain good moisture in the grass by watering 3-4 times per week and check the depth of the watering with a screwdriver after you water.  The humidity can also bring the potential for turf diseases if you get carried away with watering or water at night so make sure you have that clock set for the right amount of time and early in the morning around 5 am.  Watering at night will leave moisture on the grass and with our heat and humidity it can produce disease symptoms in turfgrass but most diseases are very rare here in Arizona unless the lawn over continually saturated.  It is better to be safe and water early so you are not only efficient, but it allows the water all day to dry off the leaves. 

Take a look at my pictures and see if it is anything you are seeing at your house.  It is a very common sight right now and all that needs to be done is a little thatching or verticutting to give the grass somewhere to grow.  Use this season to your advantage and you will be amazed at just how much these desert acclimated grasses love the heat, humidity, and rain.


  • My tip for the week is to use the weather to your advantage.  It should be easy to remember that everything we hate about the weather our grass loves so that means feed it, and push the growth unless you have paspalum.  If you have paspalum just sit tight and let the grass grow.

Please take a look at my past blogs for more information on keeping your sod looking the best in the neighborhood.

Until next time,