Question
We installed emerald Zoysia about 8 weeks ago and it is lumpy and spongy (really spongy) We tilled entire yard sanded and retilled and leveled. It was a perfect install for us and it has become real spongy and I am not sure of what to do?

Answer
You seem to have done everything right and I really cannot explain the sponginess. Have you tried lifting any of the sod pieces? You might be able to examine the ground below and see what is going on? If it is not the soil, then it is something in the sod pieces. I cannot imagine what it could be. Unless... there is a massive water leak under the lawn somewhere.