When the soil is soft, well drained and moist. In general, sod should be laid in spring before any summer moisture has been lost from the ground. Before you buy sod for your next lawn make sure it’s ready to lay. Look for a healthy leaf color and fresh root development (if it comes with roots). Also check for leaves that are dry or curled up at the base; these signs mean that the grass hasn’t had enough time to develop proper root growth and will die quickly once transplanted into your yard.