Do I Put Fertilizer on Top of Sod?

Benefits

• Fertilizers act as soil supplement and help lawns grow healthily at the appropriate times. Fertilizers encourage good root growth, especially in new sod, and keep the grass looking healthy and green. Adding fertilizer at the wrong time may limit or stunt sod growth, so make sure to apply the fertilizer correctly. When in doubt, consult with your sod company for care questions.

Timing

• Allow your newly laid sod to root strongly and fuse together before you mow or fertilize it. Check for rooting by pulling up on the end of a sod piece, if the piece doesn’t come up it has rooted; recheck a few other spots on the lawn to make sure for uniform growth. Although JB Instant Lawn suggests that you fertilize 30 days after installation, it may take five to seven weeks after installation before the sod has taken root. Exact timing depends on your area of the country, and the type of grass you chose.

Product

• Conduct a soil test to determine what elements you lawn is lacking, and then select an appropriate fertilizer based on your needs. As a rule of thumb, most lawns require a complete fertilizer such as 2-1-1 or 4-1-3, suggests the University of Rhode Island. Follow the manufacturer’s instructions for application methods and quantities, which may vary greatly upon your soil condition or type of sod you have. Depending upon the type of fertilizer you choose, you’ll likely need to apply fertilizer every four to six weeks for new sod, and one final time before the end of the growing season. Once the sod is established, you’ll fertilize closer to the normal four to five times a year.

Warnings

• Avoid adding nitrogen-rich fertilizers to dormant grasses, suggests an article on the All About Lawns website; fertilize during the active growing season instead. Adding fertilizer when the grass is dormant — such as during the winter — may cause weeds to grow instead of the grass.