Brown Patch Disease
Cool-weather, fungal disease of St. Augustine. Brown leaves pull loose easily from the runners. Small spots in lawn grow into large circles that look bad and weaken the turf but rarely kill the grass. Soil health, drainage, and low nitrogen input are the best preventatives. Treat diseased turf with cornmeal at 10- 20 lbs. per 1,000 sq. ft. or dry granulated garlic at 2lbs. per 1000 sq. ft. Spray Garrett Juice with Bio Wash (to clean plants) added. Good quality compost can also be used as both a preventative and curative for brown patch.
Q: have crop circles in my St. Augustine. The grass in the area is "bladeless" though the "runners" are still mostly green and almost as abundant as those in non-affected areas. I am 100% organic with regular applications of whole ground corn meal, corn gluten, and lots of molasses (sandy soil). My last application of corn gluten and molasses was about three weeks ago. I have "treated" the crop circles to an additional heavy dose of whole ground cornmeal. C.P., Roanoke.
A: No more cornmeal. You may have used too too much already. Drench the area with garlic tea cut back on the irrigation.