After recently installing a patio in my back yard, my yard was torn up, so I had to plant new seed over a large area. I'm in central Illinois with good black dirt and I researched the best grass for the area. I got a mix of perennial rye and Kentucky bluegrass from a very reputable seed company. I tilled the ground first and used a starter fertilizer. After planting the grass in March, the rye came up very quickly a couple of weeks later and it was very nice, full, and even. I watered it quite a bit, and by May, you could see the bluegrass filling in. After I was able to mow, I made sure to only mow when it was dry, and the blade was sharp on the mower. I raked every time to ensure there were no clippings left behind. A few weeks ago I noticed the bluegrass was taking over, and you couldn't see too much of the rye any longer, which I thought was great. However, it is now thinning way out and has many bare spots. What isn't bare has browned quite a bit. Over this time, it has been extremely hot, but it has also rained quite a bit and the ground has stayed quite wet. I haven't seen the need to water because of this, but don't know what to do. I thought about using a slow release fertilizer, but I'm concerned that it'll burn up and nothing will be left. I've also thought maybe I should wait it out and overseed with straight bluegrass this fall. Any thoughts on what I should try would be greatly appreciated.