When to Fertilize Your Grass: A Complete Guide

Timing fertilizer applications correctly will ensure your lawn flourishes

A toddler holding a football running along her father and her dog in the garden
Photo: Carlos G. Lopez / Moment / Getty Images
A toddler holding a football running along her father and her dog in the garden
Photo: Carlos G. Lopez / Moment / Getty Images
Mariel Loveland
Written by Mariel Loveland
Contributing Writer
Updated February 15, 2024

Highlights

  • It’s vital to fertilize when grass is actively growing.

  • The type of grass and your home’s location will determine when to fertilize.

  • Overfertilization can damage and kill your lawn.

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If your lawn lacks that lush look, you may be ready to give it a nutrient boost with the help of fertilizer. However, it's essential to know when to fertilize grass to help it grow greener than ever. However, you’ll need to learn the best methods of spreading fertilizer, some crucial mistakes to avoid, and when to hire a fertilizer pro to jump start your yard.

Angi Tip
When working with lawn fertilizer and other chemicals, take measures to prevent the products from contacting your skin and eyes. Be sure to wear protective gear like gloves and a dust mask to stay safe.
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Content Editor, Angi

What Does Fertilizer Do?

Fertilizer has three main ingredients, which are nitrogen, phosphorus, and potassium. The combination of these powerful compounds enrich the soil's nutrients, which helps grass and plants grow healthier. Soil can lose its nutrients from events such as leaching, erosion, and plant uptake.

So, utilizing the correct fertilizer based on what your grass needs can help replenish the nutrients and help restore your lawn to its previously vigorous state.

When to Fertilize Grass for the Best Results

Timing when to fertilize your lawn is important, but it depends on your location and the type of grass. You should fertilize when your grass is actively growing, which is typically between the last spring frost and the first autumn frost. Knowing your grass type and growing zone is essential to figuring out when to fertilize grass that yields results and prevents harming. To ensure you fertilize your lawn at the ideal time, consider hiring a local fertilizer service for high-quality results.

Time of day is another important factor. The best time to apply lawn fertilizer is in the morning when your grass is cool and slightly damp—just ensure it isn't too damp. Watering a damp lawn can lead to fertilizer burn since it allows granular fertilizer to stick to grass blades.

When to Fertilize by Grass Type

Identifying your type of grass will help you to determine when to fertilize your lawn. The two primary types of grass in the United States are categorized as cool-season or warm-season grass. Here's a breakdown of each type of grass and their growing locations.

Cool-Season Grass

Cool-season grasses, such as fescue, ryegrass, and Kentucky Bluegrass are found in the Northern regions of the United States. They grow best in cooler temperatures and thrive in temperatures between 60 to 75 degrees Fahrenheit.

Cool-season grasses will enter dormancy when temperatures fall consistently below 50 degrees Fahrenheit and can go dormant in the summer when the temperature is above 90 degrees. In other words, the ideal growing seasons are fall (the primary growing season) and spring (the secondary growing season).

The best time to fertilize cool-season grasses is in the fall since it's meant to support the most active growth period and foster healthy root growth. Fertilize early enough to allow several weeks before the first hard freeze when it jumps back into dormancy.

If your lawn needs it, you can fertilize again in the spring. You can hire a local soil testing company to make sure. If you do need to feed your lawn, apply a slow-release fertilizer in late spring, after you've given your grass time to snap back from winter dormancy.

Warm-Season Grass

Warm-season grasses, such as Bermuda, Zoysia, Centipede, and St. Augustine Grass thrive in hotter temperatures and grow in the southern regions of the United States. They grow best when temperatures are between 75 to 90 degrees Fahrenheit. Warm-season grasses tend to grow during the summer when temperatures are optimal for their needs.

If you live in a transitional zone, you may have both types of grass. You'll notice warm-season grasses turn brown after the first fall frost, while healthy cool-season grass stays green year-round. If you're still not sure what type you have, a lawn care service in your area can help.

Depending on your climate and soil quality, fertilize warm-season grass between two and four times a year (or about every four to eight weeks during the growing season.) Fertilize warm-season lawns in the spring after the last frost when grass is out of dormancy and growing. You can fertilize a second time in the late summer or early fall. You want to make sure it's after the summer temperatures peak so you don't burn up the grass. If your lawn needs it, you can put down a third application in the fall, about six to eight weeks after your summer application.

However, it is essential not to over fertilize and always follow the manufacturer's instructions to ensure you properly apply the correct amount and wait the allotted time needed between applications.

How to Choose the Correct Type of Fertilizer

It’s also essential to choose the correct fertilizer for the type of grass and the condition of the soil. Soil testing can determine if your soil lacks specific nutrients so you can purchase the correct fertilizer.

Fertilizers come in liquid and granular form, and the type you choose determines how quickly they distribute nutrients into the soil. The slow-releasing fertilizer will release nutrients over an extended period, whereas fast-releasing fertilizers make nutrients available immediately.

You should also consider whether you’re fertilizing a new lawn or an existing lawn. That factor can determine whether you begin with a starter fertilizer and then switch to a general fertilizer.

When to Avoid Fertilizing Grass

While fertilizing your lawn is a good idea, too much of a good thing can be harmful for it. Overfertilization can thwart new growth and leave your lawn vulnerable to pests and disease. As a rule, you should never use more than 1 pound of nitrogen per 1,000 square feet in a single feed.

Here are some other instances to avoid fertilizing your lawn:

  • Grass is dormant

  • During extreme heat

  • During a drought

  • Before a heavy rain

  • Right after a heavy rain

Is It Worth Fertilizing Your Lawn?

Fertilizing your lawn can help your grass grow healthy and strong. Plus, it makes your yard visually appealing. The cost of this service depends on various factors, such as the size of your lawn, the type of fertilizer, and whether you hire a professional. The average cost of hiring a pro to fertilize a one-acre yard is between $500 and $600.

You can fertilize your lawn yourself, but you will need to purchase a spreader and dedicate several hours to the task. You may want to hire a lawn fertilization service near you so you can avoid the risk of overfertilization or deal with ensuring you fertilize at the right time. A professional will take the guesswork out of this task and keep your lawn looking lush.

Frequently Asked Questions

Your lawn will have visible signs if it needs fertilizing. If your grass looks discolored, is slow growing, looks thin, or your yard has bare spots, then it probably needs to be fertilized to give it the nutrients it's lacking. You should also keep an eye out for weeds and pests because they can also be signs of a struggling lawn.

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Learn more about our contributor
Mariel Loveland
Written by Mariel Loveland
Contributing Writer
Mariel is a writer from New York City who has a passion for helping renters and homeowners make their space unapologetically their own—and save a few bucks along the way.
Mariel is a writer from New York City who has a passion for helping renters and homeowners make their space unapologetically their own—and save a few bucks along the way.
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