Is it important to fertilize a lawn in the fall?

By the end of the summer months, your lawn could easily be showing signs of stress from the heat, from the lack of rainfall, from wear and tear or even possibly from damaging insects. If your lawn goes into fall season without some post-summer recovery care, you can expect a less than vibrant and probably patchy lawn in the spring.

Fertilizing a lawn in fall helps the grass prepare for winter by strengthening its roots and storing nutrients for a strong start in the spring. It simply leads to a healthier and greener lawn.

Perk your lawn up after a tough summer

Each fall, the weather becomes cooler and the days are shorter. The growth of grass blades slows down. During this time, while the top growth slows, you might think that it’s over for the season. But that’s not true. The roots continue growing long after the blades have stopped and are still active until final freeze-up.

The nutrients you apply during the fall are absorbed directly by the root system. This process strengthens the lawn’s root system throughout the fall and will provide your lawn with reserves to draw from in the spring. Truly, the fall application of fertilizer is especially important for the overall health of your lawn.

What is the best month to fertilize your lawn?

There are two possibilities to consider: early fall to recover from summer stresses and/or late fall for winter nutrient storage and early green-up.

When's the best time to put down fertilizer?

Late August or early September is the traditional timing. Fertilizing at this time goes a long way to perk up your summer-stressed lawn. As the fall season progresses, you’ll find that along with the fertilizer, the cooler, wetter weather is quite conducive to a good grass recovery.

This is also the best time of year to repair and seed dead patches, or to topdress your lawn (refer link to topdressing article).

What's the best fertilizer to put on in the fall?

You apply a typical fall fertilizer such as C-I-L IRON+ 22-0-12 or C-I-L SO-GREEN 12-0-18 in late August or early September.

How late into fall can you fertilize?

This is a newer method of looking after a lawn in the fall. It’s what many golf superintendents use.

After the lawn has quit growing but just before freeze-up, you fertilize with a high nitrogen fertilizer (that’s the first number on the bag). If you feed your lawn late fall, consider that this will replace your normal fertilizing next spring. You can skip early spring fertilizing, as the nutrients are stored in the roots already.

The nitrogen will extend the greening period in the fall even if the grass isn’t growing. Picture all the lawns on the block with only yours greener than the rest. But also, it will be the first green lawn in the spring.

What’s interesting about this late application is that in the following spring, the lawn is green without stimulating excessive top growth, as you would find with early-spring-applied fertilizer.

University trials were done by dividing the turf plots in half: late-fall-fertilized on one half and early-spring-fertilized on the other half. Both were treated with the same high nitrogen fertilizer. The following spring, the fall-fertilized half was quite green early on, and the spring one was not. The greening on the spring-applied one did catch up later, when that fertilizer came into effect.

The surprising result was that the spring one required more mowing.

How often should a lawn be fertilized?

No matter what, you really need to do the early fall application to help your lawn recover. The late fall application can be done mostly as a preparation for next spring. But it is worth it.

For the best lawn, fertilize 3 times a season: