Before laying new sod, old sod must be removed along with weeds, debris and rocks, all of which will prevent new sod roots from reaching the soil below.
New sod laid on prepared soil will take two to three weeks to develop a strong hold in the soil. With proper site preparation and a strict watering schedule, sod roots will grow deep into the soil.
Old sod must be removed before purchasing new sod. If the sod is purchased before the soil is ready, the sod would need to sit rolled up on a pallet. If left to sit longer than a day or two, the sod will dry out and turn brown.