When Is It Too Cold To Fertilize Your Lawn?

Although fertilizing your lawn is essential for lush, thick grass, there are certain times of the year when you shouldn’t fertilize. Generally, you should fertilize your lawn a minimum of twice per year, as this gives your lawn an extra boost of nutrients to help with growth. 

But when should you stop fertilizing your lawn for the year? Can it be too cold to fertilize your lawn? It can get too cold to fertilize your yard, and this is in early to late fall for most areas. Need more information? Keep reading for a guide about fertilizing your lawn in the brisk fall weather!

What Temperature Is Too Cold To Fertilize Your Lawn?

At a certain point in the year (in many continental U.S. climates), the temperature eventually drops too low for grass to grow actively. The time of year when the temperature reaches this point varies for every area, so for some folks, the last lawn fertilization will be in late summer to early fall.

The exact temperature that indicates it’s too cold to fertilize your lawn varies based on your grass type and when it enters dormancy. Once the grass enters a dormant state, it doesn’t grow nearly as fast, so the high amounts of nutrients in the fertilizer go unused. So, you’ll need to determine the temperature at which your grass goes dormant. 

For cool-season grasses, dormancy begins later in the season, as these grasses thrive in cooler temperatures. The roots can remain active in cooler temperatures but usually, slow activity when heavy frost sets in. Generally, these grasses enter the dormant state at around 45 degrees Fahrenheit and are entirely dormant by the time the temperatures consistently remain below freezing. 

On the other hand, warm-season grasses don’t hold up as well in cool temperatures (as the name implies), so they enter their dormancy period earlier in the season. For the most part, these grasses enter the dormancy period when the temperatures regularly fall below 65 degrees Fahrenheit.

In general, you should avoid fertilizing your lawn when the temperatures regularly dip below 50 degrees Fahrenheit. For your fertilizer application to be helpful for your lawn, the grassroots need to be active, so once your grass enters dormancy, avoid fertilizing the yard. 

Is It OK To Fertilize The Lawn In Cold Weather?

Milorganite 32 lb. Slow-Release Nitrogen Fertilizer

Generally speaking, it’s best to avoid fertilizing your lawn in cold weather if the grass is dormant. However, ‘cool weather’ can be subjective, as 65 degrees might feel chilly in deep southern states. In contrast, 65 degrees Fahrenheit might feel pleasant or warmish in cooler northern states (particularly those bordering the Canadian border). 

That said, these areas have their grass types, as southern portions of the United States usually boast warm-season grasses (these thrive here), and northern parts have cool-season grasses. So, determining the temperature at which you should stop fertilizing is relatively simple.

However, if you live in the “transitional zone” of the U.S., which is a band across the middle of the continental U.S., determining this gets a bit trickier. In many cases, a mixture of warm-season grasses and cool-season grasses is scattered throughout these areas, so deciding when you should stop fertilizing might not be as cut and dry. 

If you live in the transitional zone, do some research on common grasses in your area (if you don’t know what type of grass you have), or contact a local lawn care professional for assistance in determining the type of grass you have. Once you determine your grass type, you can plan accordingly based on what temperature it goes dormant. 

When Should You Not Fertilize Your Lawn?

When the grass composing your lawn is dormant, you don’t need to fertilize your lawn. The dormant grass won’t require the amount of nutrients in fertilizer quite yet, as it isn’t growing vigorously. 

In the mid to late spring, when the soil warms up and your grass begins growing again, you can fertilize your lawn. Be sure not to fertilize too early, as this could give the weeds a head start. On top of that, fertilizing too early can encourage shoot growth instead of root growth, which is essential for a healthy, robust lawn. 

In the fall, it’s best to stop fertilizing your lawn when the grass goes dormant. As mentioned, the grass won’t utilize the nutrients from the fertilizer due to slowed growth, so you don’t need to fertilize. 

What Are The Best Times Of Year To Fertilize My Lawn?

Milorganite 32 lb. Slow-Release Nitrogen Fertilizer

As mentioned, you should fertilize your lawn at least twice yearly to promote healthy, weed-resistant growth. Spring and early fall are usually the best times to fertilize, as your yard might need an extra boost. 

In the springtime, your lawn is coming out of winter, so fertilizer gives the roots the nutrients they need to grow. In the fall, your yard is preparing to enter winter, and the fertilizer offers nutrition to foster strong root growth. 

However, while spring and fall are the best times of year to fertilize your lawn, you need to be careful that you don’t fertilize too early/late. The grass needs to be active and out of its dormancy for your fertilizer to be effective. 

Fertilizing too early or late in the season is unhelpful for your lawn, as the grass roots may not be active due to dormancy. In the fall, it’s best to use a fertilizer with lower nitrogen content. Since the nitrogen in fertilizers promotes shoot growth, opt for a fertilizer with less nitrogen, as the grass will soon enter dormancy. 

Aside from fertilizing in these seasons, it doesn’t hurt to fertilize your lawn multiple times throughout the growing season (if possible). For example, if you decide to use a slow-release fertilizer, you can reapply every six to eight weeks. Or, if you use a fast-release fertilizer, you can reapply every four weeks. 

When you fertilize your lawn on this schedule, try to plan it accordingly based on average temperatures in your area. Once the ground thaws and temperatures rise, apply fertilizer to help your lawn recover from winter. Reapply the fertilizer before the summer heat, as this will give your lawn the extra boost it needs to prepare for the high heat and accompanying dryness. 

Then, reapply the fertilizer again in the late summer or early fall, depending on when your grass goes dormant and the temperatures drop. Maintaining a regular fertilizing schedule can encourage healthy growth throughout the growing season and help your lawn bounce back after heat, drought, and cold. 

Consult a local lawn care professional for assistance if you’re unsure how often or when you should fertilize your lawn. This might be worthwhile, even if you have a general idea of what the fertilizing schedule should look like for your grass type.