Q.St. Augustine maintenance
Is it advisable to dethatch St. Augustine Grass zone 9 . How deep can you go without hurting or
completely ripping it up? Any advice for this process would be appreciated. Thanks Cindy

St. Augustinegrass lawns don’t usually have a thatch problem unless they were over-fertilized and were mowed infrequently in the past. Before you dethatch, go out and examine your lawn grass. Is the grass growing on the soil or on a layer of thatch? If the thatch is less than ½ inch thick, you should not dethatch.
https://www.gardeningknowhow.com/lawn-care/specific/st-augustine-grass/st-augustine-grass.htm