From fried rattlesnake to chicken fried steak, we Okies aren’t afraid of a little batter and oil. But the one thing we don’t want fried? Our turfgrass. The following fall lawn care checklist for Oklahoma City will help you avoid the scorched appearance of a dying lawn and instead enjoy the beauty of a healthy green one.
Our warm- and cool-season lawns are subject to bitter northern winds and blistering hot summers here in the transition zone. To ensure your autumn lawn survives the winter and greens up in spring, follow these 10 simple steps:
- Rake the leaves
- Dethatch the lawn
- Aerate the soil
- Overseed
- Fertilize
- Apply pre-emergent herbicide
- Time the last mow
- Continue to water
- Winterize your irrigation system
- Prep the garden beds for winter
1. Rake the leaves
A layer of leaves spread across the yard isn’t so healthy for your turf. As the Shumard oak leaves come falling onto your Oklahoma City lawn, it’s time to grab that rake.
A lawn littered with leaves will struggle to remain strong before the winter hits. Here’s why:
- Too many leaves in the yard will prevent your turf from photosynthesizing, the process by which your grass uses sunlight to make its food. A thick layer of leaves will hinder any sunlight from reaching the blades, causing the turf to die.
- Leaves make great real estate for pests and diseases, which can weaken your turf.
How often should I rake? Rake dry leaves every few days and wet leaves as soon as possible.
2. Dethatch the lawn
Leaves aren’t the only thing that can weaken your turf this fall. Thatch also causes turf problems (but only when there’s too much of it).
What is thatch? Thatch is the layer of dead and living organic matter that accumulates between the turf blades and the soil’s surface. Thatch will often decompose. But once the accumulation of thatch exceeds its decomposition rate, thatch becomes a nuisance in the yard.
How much thatch is too much? Thatch under ½ inch thick can do your grass some good. A thin layer of thatch acts as mulch for your turf and helps the soil retain moisture. On the other hand, a thatch layer that’s ½ inch thick or more should be removed. Too much thatch can:
- Become a breeding ground for pests and disease
- Encourage poor drainage
- Block nutrients, water, and oxygen from reaching the root system
- Prevent herbicides, fertilizers, and insecticides from working effectively
When to dethatch:
- Fall is the perfect time to dethatch your cool-season lawn, such as tall fescue or perennial ryegrass. Since fall is the active growing season for cool-season grasses, your thriving turf will have little trouble healing after an invasive treatment like thatch removal.
- Late spring through early summer is the best time to dethatch your warm-season grasses, such as bermudagrass or zoysiagrass. Warm-season grasses aren’t actively growing in autumn, which means they’ll have trouble healing if dethatched right before winter.
How to dethatch: You can dethatch the lawn using a power rake, verticutter, or dethatcher. Or, you can hire a local lawn care pro to take care of the job for you.
3. Aerate the soil
Another lawn care treatment to perform on your cool-season turf this fall is aeration. Take on the job yourself using an aerator, or hire a professional.
What is aeration? Aeration is the process of removing small cylindrical plugs of soil from the ground to relieve soil compaction. The small holes are about 2 to 3 inches deep and allow water, oxygen, and nutrients to reach the roots.
When to aerate:
- Fall is the best time to aerate cool-season turf. Similar to thatch removal, aeration is an invasive treatment, and your grass will heal itself best in fall.
- Aerate your warm-season turf in summer when it’s actively growing and can recover.
Ever wonder why your neighbor has a flourishing lawn while yours is thinning and covered in patches? The secret to achieving a carpeted lawn is to prevent patches before they appear instead of trying to repair them after they occur.
4. Overseed
The chances are good that your neighbor is planting new grass seed every chance they get, even on an established lawn. Routine overseeding ensures your property is always fresh with new growth to replace any fading grass.
What is overseeding: Overseeding is the spreading of new grass seed over an already existing lawn. You can spread grass seed by hand or using a lawn spreader.
When to overseed:
- Overseed your cool-season grass in early fall, at least 45 days before the first frost. The Big Friendly is in U.S. Department of Agriculture hardiness zone 7, which means the first frost will likely occur sometime between October and early November.
- The best time to overseed warm-season lawns is spring through early summer.
Pro Tip: The more soil you expose your grass seed to, the more likely it will successfully take root. You can increase soil exposure by aerating or dethatching the lawn before you overseed.
5. Fertilize
As the mercury begins to drop, it’s tempting to throw some fertilizer over your lawn. After all, you want the turf to be well fed before Old Man Winter arrives, right? Well, not exactly.
Fertilizer isn’t always what your lawn needs before winter, and you certainly don’t want to spread fertilizer willy-nilly. Applying the wrong amount of fertilizer, or the wrong kind is unhealthy for your turf.
Before you add any fertilizer to your lawn this autumn, there are two items to consider:
- Soil testing
- Whether your grass is a cool-season or warm-season turf
Why soil testing is essential: Testing your lawn’s soil reveals many factors regarding your lawn’s health and how you can best remedy its health with fertilizers and soil amendments. It’s not a good idea to guess what your lawn needs and potentially harm it with the wrong fertilizers. Instead, rely on a soil test that reveals what fertilizer and amendments your lawn needs to stay healthy.
You can conduct a soil test at home with a soil testing kit. Or you can send a soil sample to a lab, such as Oklahoma State University. A soil test performed in a lab will often uncover more information about your soil than a test done at home.
Why grass type is essential:
- If your lawn is a warm-season turf, it’s best not to fertilize in fall (unless your soil test recommends otherwise). Fertilizing warm-season grass in fall will encourage growth that’s too tender to survive the winter temperatures. The best time to fertilize your warm-season grass is in spring and summer, during its active growing season.
- Apply a majority of nitrogen fertilizer to your cool-season lawn in the fall. Hot summers put a lot of stress on cool-season grasses, making fall fertilization a great way to rejuvenate before winter. According to the Purdue Extension, fertilizing cool-season turf in fall:
- Promotes summer recovery
- Enhances shoot density
- Maximizes green color
- Prepares the turf for winter
- Does all of the above without a growth surge
What does N-P-K mean? Most fertilizers contain a ratio of nitrogen (N), phosphorus (P), and potassium (K). Fertilizer labels often display the ratio in the order N-P-K.
For example, a fertilizer package displaying 24-25-4 means it contains 24% nitrogen, 25% phosphorus, and 4% potassium. A soil test will reveal the best ratio for your turf.
6. Apply pre-emergent herbicide
Are weeds cropping up in your winter lawn? Consider applying a pre-emergent herbicide, a chemical barrier that stops those nuisance plants from invading your yard.
Why are weeds bad for my lawn? Weeds compete with your grass for oxygen, nutrients, and water. The depletion of valuable resources causes your turf to weaken and become vulnerable to pests, diseases, and more weeds.
What are post-emergent herbicides? Pre-emergent herbicide targets weeds before they’ve grown and does not kill established weeds. Post-emergent herbicide, on the other hand, kills established weeds.
A note about herbicides: You’ll want to avoid applying herbicide and spreading grass seed near the same time. Herbicide can prevent grass seed from growing just like it prevents weeds from growing. You may need to wait several weeks after an herbicide application or until spring before you can overseed. You’ll need to determine on your own which fall task is more important for your lawn.
Pro Tip: Weeds usually won’t occur if the turf is healthy. If your lawn is experiencing excessive weeds, there may be an underlying issue that an herbicide alone cannot correct.
Always read and follow the product’s instructions before applying the herbicide.
7. Time the last mow
Once you notice your autumn lawn has stopped growing, it’s time to perform the last mow of the season. It’s important to mow your lawn before winter arrives; otherwise, long winter grass becomes susceptible to unsightly matting and snow mold.
How low should I mow? You’ll read many places online that you should cut your grass lower than usual on the last mow. However, mowing lower than usual might not be the healthiest choice for your lawn. The University of Arkansas System Division of Agriculture and the Colorado State University Extension recommend keeping your mowing height the same in fall.
Follow the one-third rule: Never cut off more than one-third of your grass’s length. Cutting off more than one-third of the blade’s length can stress the grass and make it susceptible to weeds, pests, and disease. For example, if your grass is 3 inches tall, don’t cut off more than 1 inch.
Mowing heights: The Oklahoma State University Extension recommends the following mowing heights of common Oklahoma grasses for September through April.
| Grass type | Recommended mowing height September through April (inches) |
| Bermudagrass (Warm-Season) | 1 – 1.25 |
| Buffalograss (Warm-Season) | 2 – 3 |
| St. Augustinegrass (Warm-Season) | 3 |
| Zoysiagrass (Warm-Season) | 1 – 1.25 |
| Kentucky Bluegrass (Cool-Season) | 2.5 |
| Perennial Ryegrass (Cool-Season) | 2.5 |
| Tall Fescue (Cool-Season) | 2.5 |
8. Continue to water
The summer heat might be waning, but that doesn’t mean you should stop watering your turf. Make sure to keep your lawn well-hydrated so that it has a healthy root system before the winter chills.
Have questions about watering your grass? The following tips might help:
When should I water my lawn: According to the Oklahoma State University Extension, it’s better to water your grass when it shows visible signs of thirst than water based on a set schedule. Watering the lawn according to a schedule instead of paying attention to your grass’s needs could cause you to overwater. Signs that your turf needs watering include wilting and a blue-grayish appearance.
The best time to water your turf is in the early morning, ideally before 8 a.m. Avoid watering later than 10 a.m. as the sun will quickly evaporate the water. Evenings are not a good time to water because the water will cling to the blades overnight, creating a hospitable environment for pests and disease.
How often should I water my lawn: Water your lawn infrequently for long periods to promote a deep, healthy root system. Don’t water frequently for short periods, as this encourages a weak, shallow root system.
How much water does my lawn need: Most established lawns need 1 to 1 ½ inches of water per week. Dormant lawns typically require ½ inch of water per week. How much water your lawn needs per week will vary depending on many factors, such as:
- Wind
- Rain levels
- The slope of your lawn
- Air temperatures
- Your turf type’s drought tolerance
- How much moisture your soil retains
- How often your turf shows signs of wilting or has a blue-greyish appearance
Pro Tip: As the autumn days get colder, only water the lawn when the temperature is above 40 degrees. Although the air temperature might not be freezing, cold winds can make tiny droplets of water freeze to grass. A layer of ice on the lawn that persists for more than a month can suffocate the grass.
9. Winterize your irrigation system
No Okie wants to stress over broken pipes, especially on game day! Remember to winterize your irrigation system and drain it of all its water. Otherwise, the remaining water leads to frozen pipes, broken sprinkler heads, and cracked plastic. Drain the irrigation system this fall so you can count on a working system come spring.
10. Prep the garden beds for winter
The last item on your to-do list has less to do with your turfgrass and more to do with your front yard’s appearance. A green lawn won’t make much of an impression if unflattering flower beds surround it. Give your flower beds a health and beauty boost by spreading mulch.
Advantages of mulch: Mulch helps retain moisture in the soil, adds texture to the flower beds, and regulates soil temperatures. Organic mulches, like wood chips and shredded bark, will even add healthy nutrients to the soil.
Oklahoma City is familiar with fluctuating temperatures. Don’t let an unexpected warm spell in winter cause your flowers to germinate too early. Mulch helps insulate the ground and keeps it frozen even when air temperatures are unusually warm.
How much mulch do I need: A 2-inch layer of mulch is enough for your flower beds to reap its benefits. If your flower beds have a layer of old mulch, fluff the old mulch with a rake before adding any new mulch. Fluffing the mulch helps ensure it doesn’t become too compact.
Fall TLC brings green spring lawns to Oklahoma City
If you want a beautiful lawn come springtime, fall is when you’ve got to start prepping your grass for success. Fall lawn care might feel unnecessary, but it’s an essential part of maintaining a healthy lawn that will survive the frosty winter.
Here in these parts, we’re dealing with the transition zone. That means you’ve got to give your warm- or cool-season lawn extra attention if you want it to prosper in our extreme seasons. And remember, the lawn care that cool-season grass needs this fall is different from what warm-season grass needs.
Don’t have time to mow the lawn? Want to visit Oklahoma City’s extraordinary museums instead of doing yard work? Hire a local Oklahoma City lawn care pro to take the job off your hands. A lawn care pro can handle fertilization, lawn mowing, dethatching, aeration, and even your spring lawn care checklist for Oklahoma City.
Main Photo Credit: Pexels
