When Is It Too Cold to Fertilize Lawns?

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Your lawn has a huge impact on the overall look and feel of your home. A green and lush lawn is welcoming and warm, whereas a brown and unhealthy yard makes your home look sad and uncared for. So to keep your lawn – and home – looking at its best, you have to make sure to perform the needed maintenance for your grass. And this includes applying fertilizer. 

Using a fertilizer ensures your lawn is getting all the nutrients it needs to be healthy and green. However, when used too much or at the wrong time, it may cause more harm than good. For instance, it may burn your grass or encourage weeds to grow. Thus, knowing when to fertilize and when is it too cold to fertilize lawns is key. To answer such questions here’s our quick guide for when to fertilize your lawn.

Know Your Grass Type

Generally, there are two types of grasses in the United States: cool-season grasses and warm-season grasses. The best time for you to fertilize depends on what type of grass you have and your location. So before we can proceed to when is the best time to fertilize and answer when is it too cold to fertilize lawns, you should first determine your grass type. 

Cool-Season Grasses

These grasses are usually found in the northern parts of the country. Some of the most common ones are tall and fine fescues, Kentucky bluegrass, and ryegrass. Their peak growing periods are early fall and early spring or just after their winter dormancy. Furthermore, they thrive in lower temperatures. In fact, in high temperatures during summer, and when they lack water, these cool-season grasses can go dormant. 

Warm-Season Grasses

If you live in southern states, these are the type of grasses you have. Warm-season grasses prefer warmer temperatures, meaning their ideal growing period is during midsummer. Such grasses can include Bermuda grass, Kikuyu grass, St. Augustine grass, centipede grass, and Zoysia grass. 

Special Consideration

Those who live in a transitional zone may have a combination of both types of grasses. If you do not know which grass type you have, look out for its behavior. Does it turn brown after the first frost? If so, then you may have warm-season grass. On the other hand, if it generally stays green throughout the year, then you may have cool-season grass. Take note, however, that cool-season grasses may die during summer when temperatures are extremely high. 

When to Fertilize Your Lawn?

Generally, the best time to fertilize your lawn is when your grass type is actively growing. So for cool-season grasses, you can do it in spring and fall. To get the best results, apply fertilizer heavily during the fall and only lightly in early spring. Make sure to fertilize before temperatures spike in summer. If you prefer to fertilize your yard only once a year, September is the best time for you to do so. 

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For warm-season grasses, the best time to fertilize your yard is during late spring and summer. If you notice your grass starting to turn green in spring, apply fertilizer. Then, you may apply the second round of fertilizer once the peak of the summer heat has passed.

When Is It Too Cold to Fertilize Lawns? 

The type of grass you have will also determine when it is too cold to fertilize your lawn. But instead of thinking about the air temperature or weather, your focus should be on the soil or ground temperature. Furthermore, pay attention to when your type of grasses are active since they will benefit more from fertilizers during that time. 

For instance, if you have cool-season grasses like Fescue, the ideal temperature to be fertilizing is when the soil reaches 50 to 65 degrees Fahrenheit. So avoid applying fertilizer when the soil temperature is lower as it is not beneficial and is considered too cold. On the other hand, warm-season grasses thrive when the soil temperature is between 64 to 110 degrees Fahrenheit. The 60s is the minimum temp range for fertilizing such grasses in spring, and anything below would be too cold. 

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To know your soil temperature, consider buying a soil thermometer. You can also check out your local university extension office or use GreenCast’s soil temperature maps.  

Now, knowing when is the right time and when it is too cold are just among the factors to consider in fertilizing your lawn. You should also choose the right type of fertilizer, how much to use, and how to apply it correctly to make sure you will have a healthy lawn all year long. Moreover, always check with your local municipality before applying fertilizer to your yard. There may be specific guidelines on how much fertilizer you should use and when to do it. 

Suggested Read: When Is It Too Cold to Mow the Lawn?

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