3 years ago i planted a new lawn Bluegrass, Fescue,Perennial ryegrass,3% Bentgrass. I used 19-19-19 and milorgonite for starter fert. Lawn came out great each year i over seed about 150 to 200 pounds on 5,500 sq ft. Last year i decided to hire out the lawn care to a pro. He told me to increase my heigth to 3 or 4 inches when cutting.I usually cut it at around 2 or 3. ( I like the fairway look)He also used lesco fert. throughout the season.It seems once the grass got taller the condition of the lawn went down hill not as green and lots of thatch. Should i do a major de thatching and plug it and overseed again and go with the shorter cut or continue at 4 inches as he recomends.Now that the snow is melting i am devistated with snow mold. Any opinions would be helpfull.this picture is at 2 inches in early july.