I posted this question in another thread, but I wanted to start a new one specifically on gray leaf spot.

Has anyone used Daconil to treat gray leaf spot In St. Augustine during the heat of the summer? Randy Lemmon recommends it, but it's not clear to me if it should only be used if the temp is less than X (seems like I may have read 85F) to avoid damaging the plant/lawn.

I'm in Houston.

I would not trust anything Randy Lemmon says. He says what he is told by those who pay him the most. He would sell his mama for the right price. Go to Neil Sperry's site and read up on gray leaf spot. It is caused by too much nitrogen being applied. Neil recommends Scott's Disease EX and I have seen the product take care of Take off root rot and other fungal diseases. You can also use Propiconazole 14.3 Fungicide and cure it. You can buy this at any Solutions store in Houston or on line. Also available at domyown .com. Hope this helps

I have used Daconil on St. Augustine in hot weather with good results. Also if you have grey leaf spot you should wait until fall to fertilize again and do not water in the evening where grass will stay wet overnight.

Ditto on any Lemon recs! He is a branding ho.