I have a yard that I picked up mid-season so I do not know how much N Tru-green has put on it. Here where I live we are going from 95 degrees to 76 degrees with pooring rain in June and July. This yard is a fescue bluegrass blend and I am wanting to put an Iron product on it to green it up, instead of pushing the nitrogen which will make the brown patch explode. Long story short the poduct I have is a granual with 22%iron and 55% elemental sulfur. I was planning on puting it down 4lbs per 1000. Do I need to worry about burn with the spikes in heat we are having.