As temperatures drop and leaves begin to fall, you might be tempted to put away the lawn care tools for the season. But fall is actually one of the most crucial times for lawn maintenance. The work you do now sets the foundation for a healthy, vibrant lawn come spring.
From managing leaf buildup to fertilizing at just the right time, proper fall lawn care prepares your grass to survive winter dormancy and emerge strong when warm weather returns. Whether you’re aerating compacted soil, overseeding thin patches, or applying that final fertilizer application, these autumn chores are essential investments in your lawn’s future health.
Lawn care can get to be a slog after a while, but don’t let off the gas in the fall. If you just don’t have the will or the time for it, consider hiring a pro.
Continue mowing until the grass stops growing
When to stop mowing: Stop mowing cool-season grass in October or November, or when soil temperatures drop to 40 degrees. Warm-season grass will tell you when it’s time to stop mowing; it will stop growing.
It’s tempting to let cool- or warm-season grass go uncut in winter, but overgrown grass can mat, which allows fungal diseases to take hold. Mowing until the grass stops growing will reduce winter damage and pest infestations, too.
But P. Agustin Boeri, assistant professor and turfgrass specialist at the Texas A&M AgriLife Research and Extension Center in Dallas, cautions against making the last cut too short.
”If the turfgrass is cut too short, it may not recover, which increases the risk of winter kill and creates open spaces where winter weeds can germinate,” he says
For more information, see Last Mow of the Season
Adjust lawn watering
When to stop watering: Stop watering cool-season grass when daytime air temperatures consistently drop below 40 degrees and nighttime temperatures fall into the low 30s. For warm season grass, stop when daytime air temperatures drop below 50 degrees.
In order to build a strong root system for winter, grass should be watered in the fall. But watering once temperatures drop below freezing (especially if the ground freezes) is a definite no. Here’s why:
- When water hits frozen ground, it turns to ice, which expands and damages the grass roots.
- A layer of ice on the grass damages the blades, plus, it prevents the soil from absorbing moisture, leaving you with mud once the ice melts.
- Even if temperatures remain moderate, remember that both cold and warm season grass go into dormancy, and overwatering dormant grass can allow fungal diseases to take hold.
For more information, see When to Stop Watering Your Lawn
Manage falling leaves
When to rake: September to December, depending on climate and tree species. Just use your head, and rake when the leaf cover gets heavy.
While dealing with leaves can be a pain in the neck (and back), allowing a heavy cover to sit on your lawn can block sunlight and air from reaching the grass. Also, decomposing leaves promote mold and fungus that can damage the lawn.
The usual methods are to rake or use a blower or vacuum to collect leaves for the compost pile or bagging. Another option: mulch with a rotary mower to fertilize the grass. But Boeri suggests being cautious with heavy leaf cover.
“Mulched leaves should blend into the turfgrass canopy,” he says. “Leaving thick layers of mulched leaves on top of the turf can smother and kill it.”
For more information, see 12 Best Tools to Use to Collect Autumn Leaves
Treat and control weeds
When to treat weeds: For both types of grass, apply pre-emergent herbicides from late August to October, or whenever soil temperatures – not air temperatures – fall below 70 degrees.
Come spring, you don’t want to see chickweed, dandelions, nutsedge, or any other common weeds that will take nutrients, water, and light away from your turf. An early-fall application of a pre-emergent herbicide is one way to prevent those surprises.
Before you buy or apply, do some research. Make sure the herbicide is compatible with your grass type and that it’s formulated for the weeds you plan to target.
Note: If you’re battling crabgrass, skip the fall application. Crabgrass doesn’t develop until late spring or early summer, so apply between mid-March to May, or when soil temperatures hit 50-55 degrees.
For more information, see What Are Pre-Emergent Herbicides?.
Remove excess thatch
When to dethatch: Cool-season grass does best when dethatched between late August and early September. Dethatch warm-season grass in the spring.
A light layer of thatch isn’t a bad thing: That organic debris insulates the soil and conserves moisture. But too much of it blocks water and fertilizer, plus creates a haven for pests and diseases.
Is your thatch too high? Use a trowel or spade to remove a plug of grass and soil. If the thatch layer is more than ½ inch, it’s time to act.
Be safe: Before using a power rake or vertical cutter, mark any sprinkler heads, water lines, and buried utility lines. For more information, see How to Dethatch Your Lawn.
Aerate compacted soil
When to aerate: Aerate cool-season grass between mid-August and October; aerate warm-season grass from May-July.
Compacted soil prevents grass roots from receiving air, water, and nutrients, eventually causing grass to thin out and die. Aeration alleviates compaction by poking multiple holes in the lawn so the grass roots get what they need.
Do you need to aerate? Push a screwdriver into the ground. If it easily slides to the handle, you’re fine. If there’s resistance, it’s time to aerate.
The preferred tool is a core (or plug) aerator, which has metal tubes that pull plugs of soil. You can rent these if you plan to DIY. Make sure the soil is moist. If not, water the night before. But don’t overdo: The tubes can plug if it’s too wet.
For more information, see What is Lawn Aeration?
Overseed
When to overseed: Overseed cool-season grass between mid-August and mid-September, or 45 days before the first hard frost. Overseed warm-season grass for winter color, between mid-October and early November. Make sure soil temperature is in the 50 to 65-degree range.
For cool-season grass, overseeding can help fill in any thin or bare spots. It also can increase the lawn’s overall density to discourage weed growth. But the new grass needs to take hold. Give it a light daily watering to keep the soil bed moist.
For warm-season grasses, overseeding with cool-season grass will bring a pop of winter color. That’s a common practice for Bermudagrass in sports fields and golf courses, Boeri says.
Usually, perennial ryegrass is preferred due to its thicker growth and deeper color.
Good seed-to-soil contact is essential, but use caution. “Scalping the Bermudagrass to its lowest recommended height is a widely used method to create a good seeding surface,” Boeri says, “ but (it) can stress warm-season grasses if done late in the season.”
For more information, see Top Overseeding Mistake to Avoid
Fertilize for strong roots
When to fertilize: Fertilize cool-season grasses between September and November; fertilize warm-season grasses between August and mid-September, but no later than the end of September.
Fertilizing in the fall helps both types of grass maintain healthy roots and store energy to survive the winter. But what to use?
- For cool-season grass, consider a complete fertilizer with a high ratio of both nitrogen and potassium. For warm-season grass, Boeri says the fall application should have 0.5 to 1 lb of nitrogen per 1,000 feet. Use a soil test to determine the rate for other nutrients.
- Don’t fertilize before a heavy rain. It can wash fertilizer off your lawn and into the storm drains. Instead, give the grass a light watering to help it absorb the fertilizer.
For more information, see When to Apply Fall Fertilizer to Your Lawn
FAQ
Oklahoma State’s extension suggests mulching, as bagged clippings can’t return nutrients to the soil. But Boeri, of Texas A&M’s extension, cautions that, like mulched leaves, grass clippings should blend into the turf. A heavy layer of clippings can smother the grass.
Pull them: This works best after a rain or watering. Wiggle the weed to loosen roots, then give it a good, steady pull.
Use tools: Hoes can pull out seedlings; hand forks and spades can lever out large root balls; dandelion pullers can take on weeds with a taproot.
Boiling water: Pour it directly on the weed. Unfortunately, it also will kill nearby plants or grass, so it’s best used on the driveway or patio.
Combination products are convenient, but have their limits. ”The timing of your pre-emergent and your last fertilizer application may not align,” Boeri says “It is also difficult to match the correct fertilizer and herbicide rates in a single product. For example, applying a weed-and-feed based on the herbicide rate could result in too much or too little fertilizer.”
Do you need help with fall lawn care?
We hope our tips will help you finish those fall lawn care chores before winter sets in. Should you need a hand, LawnLove can help. We’ll connect you with local pros who can take care of your lawn mowing, lawn aeration, and leaf removal needs.
Read more
- Benefits of Fall Yard Cleanup
- What’s the One-Third Rule of Mowing?
- What to Do With Fall Leaves on Your Lawn
- How to Use a Leaf Blower
Main Image Credit: Use a leaf blower with a bag to collect leaves in fall. Photo Credit: Saklakova / Adobe Stock
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