I live in Nebraska, zone 5 and have TTTF. I've been on an organic fertilizer for three years now. My back yard is shaded due to two big silver maples. My front is full son and has one small crab apple tree. Temperatures for the last week and unforseable future will be pushing 100. I've put my mower on the highest setting now and will test out what the lawn will do without rain help. My plan is to only water the back yard because we will be hosting this summer and I want to make sure the maples are taken care of. The front yard I won't touch until I do my fall overseeing. I want to see how long it will take to come out of summer dormancy in the fall. I will post some before pictures in a bit when I'm done mowing. I'll probably post a new picture each week to see what the lawn is doing in the heat. Everything I've read is how well an organic lawn does in heat and drought stress.