I put up $150 worth of free landscaping at a local festival in order to get my name out there and pick up a new customer. The woman who had the highest bid called me and wants to put sod down in her front yard 15'x12'. There is existing grass that is in decent shape. Am I better of spraying the grass now and killing it...or waiting until spring. Also....what is the earliest or latest in the year you have successfully installed sod. I live in Northern Kentucky just across the Ohio River from Cincinnati. Thanks.