re: Best grass to have in a shaded area

St Augustine is the most shade tolerate of the 4 warm season grasses, is that widely used in your area? But 3-5 hours still might not be enough light. I’d suggest speaking to your county cooperative extension agent/specialist. If you’re not familiar, University of Tennessee, TN Cooperative Extension Service, search for your county, there should be contact information for personnel in your county. Each county will usually have a Extension (outreach) specialist for lawn and gardens.