New sod can turn brown due to early fertilizer application, inadequate watering, soil compaction and lack of contact with the soil. New sod doesn’t need fertilizer for the first one or two months and can get burnt by it. However, it requires more water than established grass and turns brown if it doesn’t get enough. Good contact with uncompacted soil is also necessary for new sod to stay green.
Newly laid sod has shallow roots that are incapable of absorbing fertilizer nutrients. If fertilizer is applied too early, nitrogen leaches into the ground and burns brown patches into the grass. Watering can remedy this problem by reducing the concentration of nitrogen. Watering also helps new sod to establish its roots. New sod should be watered between two and four times daily for the first week.
New sod can turn brown despite adequate watering if it is laid on compacted soil. Compacted soil cannot soak in water, so the water flows away. Aerating the soil by poking holes in it can improve its ability to absorb water. New sod can also turn brown if it does not have good contact with the soil underneath. This happens when the soil settles after the sod has been laid and creates air pockets between the sod and the soil. Good contact can be established by filling in the air pockets with soil and pressing down the sod.