We all know that transitioning from ryegrass back to a warm season grass is difficult (especially for California and Arizona sod), but throw in some cooler than normal weather and now you have a battle. Every year the producers of ryegrass seed seem to make their seed a little more heat resistant in search of that year round turf. The problem with this is that we’re shortening the growing window of our warm season turf. Not to mention that cool season grasses in the desert areas use much more water than the underlying warm season turf. The solution is to aide your lawn in transition, and to get your lawn free and clear of ryegrass in the next couple weeks.

Before I go into techniques to remove ryegrass I want to make a couple points about how the average lawn looks at this time of the year. We all love our winter lawn for its color, texture, and feel, but it’s important to remember that it puts agronomic stress on your lawn. When you have two different grasses competing for nutrients, water, and sunlight you’re bound to have an “ugly period.” The turf world refers to this as the transition period. This is the period of time when the cool season grass is starting to die off slowly and the warm season grass is trying to emerge. What creates the ugly period is the competition.

(BTW…this beautiful turfgrass is NOT going through an ugly stage!)

I think it is important to remember that most warm season grasses outside of St. Augustine have little to no shade tolerance. Having a solid stand of ryegrass in the month of June is not only detrimental to your water budget it is also the equivalent of covering your lawn with shade trees. Ryegrass does not allow filtered light and will do everything it can to survive. This means using more water than is normally necessary to grow grass. The last thing anyone wants to do is use excess water, so it is best to follow my instructions below to aide in lawn transition.

While you’re transitioning your lawn it is a great time to do your monthly watering analysis. We all budget money every month knowing we can’t exceed a certain percentage of our income, and the same should be done for your water. As I said in previous blogs I know you can reduce your water consumption by 25-30% by watering wisely. Run through all of your sprinklers and check the spray patterns. Are any of them throwing water on the sidewalk? Do you have clogged nozzles? How is the coverage? Are the sprinklers throwing from one sprinkler to the next? Are there any leaks that need to be addressed? All of these items are not only crucial for saving water, they’re important for a successful transition.

I constantly harp on the need to verticut or power rake your lawn in order to optimize new growth, but how about doing so to remove ryegrass? Both of these machines slice into the turf canopy, remove dead top growth, some thatch, and also injure actively growing ryegrass. The vertical blades lift up the weak cool season grass putting stress on the grass plant. Normally hot temperatures will just wipe out the ryegrass, but the beautiful weather we have had so far this year is keeping it healthy.

Verticutting/power raking will serve a couple purposes. The first is opening up the grass plant and allowing sunlight and water to get down to the warm season turf. The second is that it is removing dead material that is using the warm season turf’s water.  If you dig your hands down into your turf you will notice several new leaf blades appearing. These leaf blades will struggle to grow if they’re being blocked by dead material on top of the grass. After you open up the turf canopy these new leaves will begin to spread and you will start to see new growth all over your lawn.

The second and easiest way to remove stubborn ryegrass is by chemically transitioning your lawn. There are several chemicals on the market now the will kill ryegrass and not damage your warm season turf. Some of the more popular chemicals being used are Revolver, Manor, Kerb, Xonerate, and Monument. There are several more on the market, but I won’t list them all here.

I will say is that it is extremely important to read the label and follow the directions. If the label says .4 oz/1000 SF, then that is the maximum rate so you don’t cause injury to the grass and surrounding areas. These chemicals usually take 7-10 days to completely kill the ryegrass. At that point you will quickly find any areas weak in warm season turf. This is a good time to cut out larger areas in a square or rectangle and replace the bare areas with sod. Most of the time you will just need a few rolls of sod to patch your lawn, but if you went into overseed with a weak or new warm season turf you may have a few more spots to replace.

After patching your bare areas it is a great time to add fertilizer. I suggest giving the lawn a push to get some quick growth. One of the easiest ways is to add ammonium sulfate 21-0-0 at 5 pounds per 1000 SF. If you have a solid stand of turf free of voids then I would stick with a balanced fertilizer such as 21-7-14. This will help both your roots and shoots. The ammonium sulfate is just going to push top growth and get those runners moving to fill in small voids.

The old philosophy on transition was to just turn your water off for two weeks and let your ryegrass die. What this theory didn’t account for was that the warm season turf needs water in order to grow. You will probably be successful killing any remaining ryegrass this way, but you won’t have a very good stand of grass underneath it. Cut you water back by 40% and let the ryegrass slowly fade away on its own. There is no need to try and keep alive a grass that has no chance of living once temperatures consistently top out over 100 degrees.

I know we all want this perfect year round grass, but remember everyone goes through the same struggles. If you’re driving neighborhoods and seeing perfect grass it is because they’re wasting water trying to keep the ryegrass alive or they did not overseed and their warm season turf is thriving. The “ugly period” isn’t that long if you follow my techniques for transition. So remember to water wisely, open up your turf plant, and be patient!

Remember, you can have a lawn and be water friendly.  Check out my last few blogs for reminders on how to do this.  Your lawn is benefiting the environment!  You might even want to forego overseeding in the winter, and use a turf colorant such as Endurant.  A warm season grass + Endurant is a perfect solution for a pretty lawn in this drought!  We’ll talk about it more in September.

If you have any questions, please hit the “Ask Jay” button at the top of this page and I will do my best to help.

Until next time,

Jay