How Late In The Fall Can You Plant Grass Seed?

How Late In The Fall Can You Plant Grass Seed

Spring is the best time to plant grass seeds, right? Not always – sometimes, the soil temperature is too cold, so your grass seed rots before the temperature reaches the optimal range. So, if you can’t plant your grass seed in the spring, how about planting in the fall?

Although it might seem counterintuitive to plant your grass seed at the summer’s end, fall is an excellent season for reseeding or establishing your lawn. Ready to learn more? Stick around to find out why fall is often the ideal time of year for planting grass seed!

Is Fall A Good Time To Plant Grass Seed?

While you can plant grass seed throughout the growing season, some times of year are better for successful planting. Ideally, you should try to reseed your lawn (or establish a new one) in late summer or early fall. The conditions are favorable for the new seedlings, so shoot for fall. 

Fewer Weeds

As the growing season comes to a close, the competition from weeds declines considerably. This is the polar opposite of spring, where weeds seem to be the first thing to appear in your garden, flowerbeds, and lawn. The lack of competition makes fall an excellent time to reseed your yard, as the seedlings will have a better chance of survival and establishment. 

Your grass seeds won’t have to compete for essential growing components like sunlight, water, and nutrients. So, if possible, try to reseed or establish your new lawn in late summer or early fall. 

Ideal Temperatures

Air and soil temperatures are a few more bonuses of planting during the fall. Generally, the summer heat is gone, so the air temperature drops to a more comfortable level. Nighttime air temperatures are much cooler, but daytime temperatures remain within a reasonable range for plant growth. 

The chill of the night helps mitigate disease activity that could threaten your new seedlings, while the warmth of the day encourages shoot and root growth. 

In addition to the beneficial air temperatures, soil temperatures tend to be at an ideal level. Generally, the soil is still warm enough to promote immediate seed germination, which kickstarts the growing process. In the spring, soil temperatures often remain colder for longer, even though the air temperatures are at a decently warm level. 

Since grass seed can rot if it lies in too-cold soil for prolonged periods, the fall and its warmer soil is an ideal time to plant. Ideally, you should plant your grass seed when the soil temperature is between the upper 60s and low 70s. In some areas, this might mean you need to plant in late summer, but in other parts of the U.S., it might point to fall planting. 

When Should I Plant Grass Seed In The Fall?

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The exact point in the year that marks when you shouldn’t plant grass seed depends on where you live. For example, the temperatures will likely remain somewhat warmer for longer if you live further south. In the lower southern states, you might be able to plant grass seeds closer to the winter than summer. 

However, if you live up north, like in one of the states along the Canadian border, you’ll want to plant grass seed much earlier. Timing is critical for the success of your newly-planted seeds. If you plant too late and the cool temperatures sweep in, your seedlings might not have enough time to germinate, establish strong roots, and mature for survival throughout the harsh winter. 

Heavy frosts can detrimentally affect fragile seedlings, so choosing the appropriate time to seed is essential. As a general rule, it’s best to plant your grass seed anywhere from four to six weeks before the first frost. 

For example, if your area gets the first heavy frost around November 1, you’ll want to have your seeds planted by the middle of September, as this gives the seedlings plenty of time to establish themselves before winter strikes. 

Dormant Seeding

Sometimes, fall might get away from you, ebbing into winter before you have the chance to plant your grass seed. If you miss the optimal seeding window, you might want to consider a practice called dormant seeding. 

With this method of seeding, you simply spread seeds over your lawn right before the snow is expected to fall. The layer of snow will protect the seeds and ensure they don’t begin germination. Instead, they’ll remain dormant throughout the winter. 

The risk with dormant seeding is the fluctuation of temperature throughout the winter. For example, let’s say winter releases its grip on your area for a few weeks, creating spring-like temperatures. After those warmer weeks, the temperature drops again, returning to the icy temperatures of winter. 

In that time, your dormant grass seeds may germinate and begin to establish. However, when the warm weeks end, the seedlings will likely be unable to survive, as they probably won’t be established enough to weather the cold. 

If you decide to use the dormant seeding method, you should prepare the soil as you normally would. Test the soil to determine what adjustments are necessary for healthy grass growth, then adjust the pH and other factors to accommodate lacking areas. 

Once the pH level is balanced, fertilize the soil and apply the grass seed with a spreader. Rake in the seeds to ensure good contact with the earth, then cover them with a quarter inch of soil for germination when the weather warms up again.

Be sure to choose a type of grass seed that flourishes in your area. If you choose the wrong type, you might set yourself up for failure right out of the gate. So, do your research to determine a suitable grass variety for your area (warm-season grasses vs. cool-season grasses). Contact local lawn care professionals for assistance if you’re unsure which type to choose. 

Remember, this method might not pay off, especially if your area experiences fluctuating temperatures in late winter. So, if you’re concerned about whether your grass seed will survive (and missed the optimal window), it might not hurt to wait until spring/fall to plant.