Don’t fertilize your lawn this winter in NJ: It’s the law

🔵 New Jersey is currently in a fertilizer blackout period

🔵 Homeowners are not permitted to fertilize their lawns during this time

🔵 Over-fertilization can cause algae blooms and harm marine life

Did you know that you can’t fertilize your lawn during the winter in New Jersey?

Since 2011, New Jersey homeowners and commercial lawn services have been prohibited from applying fertilizers to lawns during the winter months.

The fertilizer blackout began on Nov. 15 for private homeowners and on Dec. 1 for commercial lawn service. It ends for both on March 1, 2025.

This law is designed to protect the rivers, bays, and streams in New Jersey by reducing fertilizer runoff, which can cause excessive algae growth and bloom, said Tim Dillingham, executive director of The American Littoral Society.

Waterways, like people, need to have nutrients come into them to keep them healthy. But like people, if they get too much feeding, this can become a problem, Dillingham said.

Over-fertilization of New Jersey’s bays, particularly Barnegat Bay, can result in oxygen depletion in the waterways.

“So this law limits how much fertilizer we put on our lawns and when we can do that. The blackout period, if you think about it, is during the time that the ground is frozen. The grasses are dormant and really don’t need feeding at that time,” Dillingham said.

To reduce the application of fertilizer in the state, and reduce the amount of runoff into waterbodies, this law tells the folks in New Jersey to not apply fertilizer between Nov. 15 and March 1.

But do people really fertilize their lawns in the winter?

Suppose New Jersey experiences some mild days in January and February. In that case, many people think they’re helping their lawns become lush and green in the springtime by dumping an extra dose of fertilizer on them, Dillingham said.

But many people don’t understand that what they put on their lawns ends up in streams, rivers, and bays.

The problem is that the fertilizer does not soak into the grass because the lawn is frozen and the grass is dormant. So, the fertilizer runs off into the waterways.

When that runoff happens, it can cause damage. Dillingham said excessive nutrients like phosphorus and nitrogen from the fertilizer cause excessive algae growth and bloom. When that algae dies, it decomposes and zaps up the oxygen in the bay, destroying the value and the functioning of the bay for fish, crabs, oysters, and clams.

“That’s what we see happening in Barnegat Bay. So the law was an attempt to help reduce excess fertilizer, excess nutrients going into the water,” Dillingham said.

The law also sets the limits on how much phosphorus and nitrogen can be in fertilizers sold in New Jersey. Dillingham said the bottom line is to apply the fertilizer according to the directions that are on the bag.

“If you do that, you’ll be using the fertilizer safely, protecting our waters, and probably still have a nice, green lawn,” Dillingham said.

He added that it is vital to give your lawn a rest in the winter. There will be plenty of opportunities in the spring and summer to fertilize your lawns.

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