What are these light brown rings in my lawn?

There’s a surefire way I can tell fall has arrived in North Texas beyond looking at my calendar and the cooler temperatures.  We start getting phone calls from our customers about these funny brown rings in their lawn.

Brown patch is a fungus that attacks St. Augustine in the fall (and spring.)  It happens in North Texas in the fall and spring because that is when we typically have warm days and cool evenings.

This pattern can make it so your lawn never fully dries which leads to the nasty little fungus called Brown Patch.  To understand Brown Patch you need to consider that St. Augustine is a tropical plant and our North Texas summers of blistering heat coupled with cold winter days put far more stress on it than its more natural home in places like Houston or Orlando, Florida.

The stress of summer (in this instance) followed by the perfect condition of warm days and cool nights create the perfect condition for Brown Patch.

Most of the time Brown Patch is just unsightly for a while (it will go away after our first frost,) but if we have a cold enough winter, these weakened areas might suffer freeze damage.

If you want to avoid or treat Brown Patch I recommend watering your lawn in the morning so it has the best chance to dry during the day.  You can also cut back your watering in shady areas.  Instead of 30 minutes per week, try 10 or 15 minutes in those areas.
Another thing to note if you are doing your own fertilization is that Brown Patch feeds on nitrogen.  You need to avoid high-nitrogen fertilizers in St. Augustine lawns during early spring and fall.  At Village Green we use a 5-10-31 ratio fertilizer.Finally, if you see signs of Brown Patch you should treat the areas with Propiconazole.  This isn’t going to make the Brown Patch go away, but it will stop the spread into other areas of your lawn.
If you have questions or need help give us a call at 972-495-6990 or email me at [email protected].  We have been offering preventative programs for Brown Patch in North Texas for over 30 years and would love to earn your fertilization business.