Fall Lawn Care Checklist for Chicago

horizontal look at a freshly mowed lawn with a fence in the background

When the breeze off Lake Michigan starts to feel chilly instead of pleasant, it’s time to get out your fall lawn care checklist. You need to help your yard recover from the heat of summer and prepare your yard for the freezing weather and heavy snowfall ahead. 

This 11-point checklist covers watering your grass, raking leaves, testing your soil, and more. The goal? Helping your lawn to survive through winter and thrive in spring.

  1. Keep watering the grass
  2. Rake up leaves
  3. Get rid of excess thatch
  4. Aerate to improve lawn health
  5. Overseed for a thicker lawn
  6. Test your soil
  7. Fertilize with the right nutrients
  8. Prevent and kill weeds
  9. Keep mowing until the grass stops growing
  10. Drain sprinklers before winter
  11. Prepare flower beds and plants for winter

Proper fall lawn care can seem like a lot of work, but it will definitely pay off in the long run. And you always have the option to hire a lawn care pro in Chicago to mow your grass, fertilize your lawn, and tick off the other boxes on this checklist for you.

1. Keep watering the grass

sprinkler on and sitting in a yard
Mohammad Rezaie | Unsplash

Continue watering as usual during fall. The cool-season grasses that grow in Chicago need water at this time of year more than ever because fall is their growing season. If you water the lawn properly, roots will grow and spread deep into the soil, which is essential for grass to do well through winter. 

For the strongest root development, water the lawn deeply and infrequently. About 1 inch of water per week is the standard, but your specific lawn’s needs will vary. Watch for signs of overwatering or underwatering. 

When should you stop watering the lawn in fall? Don’t stop watering until the ground freezes (when your grass goes dormant for winter). You can expect the ground to freeze in late October or early November in Chicagoland. 

2. Rake up leaves

Raking up leaves is probably the most annoying fall yard chore, but it’s vital for this area’s cool-season grasses. Remember, local favorite grass types such as Kentucky bluegrass and fine fescue are actively growing throughout fall. Too many leaves building up on top of the grass can block that growth and, in severe cases, kill your lawn. 

Letting leaves build up in the lawn can have several negative effects:

  • Prevents water from reaching the grass’s roots
  • Blocks sunlight, preventing photosynthesis
  • Gives pests a place to live and reproduce in your lawn
  • Creates perfect conditions for fungal lawn diseases to develop

If you want to avoid these issues, you should rake every three to four days, or at the very least, once a week. 

3. Get rid of excess thatch

Graphic explaining thatch on grass

Why should you dethatch your lawn? When the layer of dead plant matter that naturally accumulates between the grass and the soil, known as thatch, grows too thick, it can smother the grass and invite pests and diseases. 

Some thatch is a good thing, though. It shields the grass from damage and eventually breaks down into the soil, adding essential nutrients. Thatch of ½-inch thick or less is ideal.

When should you dethatch your lawn? You should always dethatch during your grass’s active growth period so the lawn can recover quickly from any damage sustained during the process. Cool-season grass types grow actively in both spring and fall when temperatures are moderate, so you can dethatch during either growing season.

What is dethatching? Removing leaves and other debris from the surface of your lawn is not the same as dethatching. Dethatching (also known as power raking or verticutting) goes much deeper to remove debris caught between the grass and the soil. When you dethatch, you use a tool called a dethatcher (or verticutter, or power rake) with vertical blades or tines that break up the thatch and make it easier to remove.

Keep in mind, you may not need to dethatch every year. You only need to remove thatch when it’s thicker than ½ inch. You also should dethatch before aerating the lawn — more on that in a moment. 

4. Aerate to improve lawn health

What is aeration? Aeration uses a machine called a core aerator to punch holes in compacted soil. Those holes loosen up the soil and improve circulation so water and essential nutrients don’t have to work so hard to reach your grass’s roots. 

Similar to dethatching, you should aerate your lawn only during its growing season, which in Chicago means spring or fall. However, aerating in spring often results in a weedy lawn, so fall is the best time to aerate

You probably won’t have to aerate every year unless your lawn sees a LOT of heavy foot traffic, which can cause severe soil compaction. If you decide your lawn needs aeration this year, be sure to dethatch first so the core aerator can reach the soil without thatch getting in the way. 

If you want to aerate your own lawn, you can usually rent the necessary equipment from a local hardware store. Alternatively, you can hire a lawn aeration pro for a little more money than the rental and a lot less effort on your part. 

5. Overseed for a thicker lawn

infographic showing the best time for overseeding on the US map,

What is overseeding? Overseeding just means planting new grass seeds in an already established lawn. You would overseed to solve problems such as dead patches of grass or thin growth resulting from a pest infestation or lawn disease. 

When should you overseed your lawn? Even though cool-season grass types grow in fall and spring, it’s better to overseed in fall so your new grass doesn’t have to face the summer heat immediately after getting established. 

Overseed no later than 45 days before the first frost of the year. Then the new grass will have plenty of time to grow strong, deep roots before its dormant season. In Cook County and the surrounding areas, the first frost usually hits in late October. So, if you plan to overseed your lawn this fall, do it by early September

6. Test your soil

Once a year, you should test your soil to find out what type of fertilizer and additional supplements your grass really needs. Is your soil lacking in nitrogen, potassium, or another essential nutrient? Do you need to add lime to adjust the soil’s acidity? The results of a soil test will answer these questions and more. 

Get your soil tested locally through the Cook County Farm Bureau. If you already tested your soil in spring of this year, you can use the same results to choose fall fertilizers. If it’s been more than a year since your last soil test, consider getting a new test before fertilizing. 

7. Fertilize with the right nutrients

What’s the best kind of fertilizer to use in fall? That depends on your lawn’s specific needs, which you can find out with a soil test. Without conducting a soil test first, you might end up using a fertilizer that doesn’t contain the nutrients your soil lacks. 

When is the best time to fertilize the lawn? In Chicago, you should fertilize your cool-season lawn at least once a year in early September. You also can split the annual amount of fertilizer into two, three, or four applications, with a lawn fertilization schedule as follows:

Number of fertilizer applications per yearIdeal fertilizing schedule
1Early September
2Early May > Early September
3Early May > Early September > Early November
4Early May > Mid-June > Early September > Early November

For most lawns, you should use about 3 pounds of fertilizer per 1,000 square feet per year. If you choose to apply fertilizer more than once a year, split that amount in half, thirds, or fourths per application as needed.

8. Prevent and kill weeds

white clovers dotting a grass landscape
NY State IPM Program at Cornell University | Flickr | CC BY 2.0

Do you typically find tons of weeds sprouting in your lawn in spring and summer? You can prevent those weeds next year if you think a step ahead and apply pre-emergent herbicides any time between August and November

Pre-emergent herbicide kills weeds while they’re still tiny germinating seeds, so the weeds never get a chance to grow in the first place. Here are just a few of the common Chicago winter weeds you can prevent with an application of pre-emergent herbicide in fall:

  • Field pennycress
  • Horseweed
  • Shepherd’s-purse
  • Prickly lettuce
  • Red sorrel

You also may need to apply post-emergent herbicide in fall if summer weeds linger in your lawn well into September or even October. Post-emergent herbicide kills weeds that have already sprouted, so it’s only useful if your lawn currently has a weed problem. Some common summer weeds in Chicago include:

  • Bindweed
  • Buckthorn
  • Canada thistle
  • Crabgrass
  • Dandelions

9. Keep mowing until the grass stops growing 

When is it time for the last mow of fall? When you can tell your grass isn’t growing anymore, you should mow it one last time to the height you decide is best, then stop mowing until spring. 

Many experts recommend cutting the grass shorter on the last mow before winter than you do the rest of the year. The exact cutting height you should use will depend on your grass type, but in general, the last mow of the season should leave your grass about 2 to 2½ inches high. 

Be careful not to cut the grass too short, though, as this can scalp the lawn. Scalped lawns are less likely to survive winter and more susceptible to diseases like snow mold. Some experts say it’s too risky to cut grass shorter at all and recommend using your usual cutting height for the last mow.

10. Drain sprinklers before winter

sprinkler on grass shooting out water
Shaylor | Flickr | CC BY 2.0

Do you still want a working sprinkler system by the end of winter? If you leave water inside the pipes and it freezes, you might end up with nothing more than a broken, busted mess. Drain your sprinklers before the first hard freeze of the year to save them from winter damage. 

In the Chicagoland area, you can expect the first hard freeze from late October to mid-November. Early October is the latest you should winterize (drain) your sprinklers to be safe. 

How do you drain sprinklers? There are three common methods: manual drain, automatic drain, and blow-out. We’ll briefly go over each method.

  • Manual drain
    • Disconnect the sprinklers from the water supply or shut off the water source.
    • Open the valves at the ends of the pipes and let the water drain out. 
    • Drain the backflow device once the rest of the system is empty.
  • Automatic drain
    • Disconnect the sprinklers from the water supply or shut off the water source.
    • Run one or more sprinkler heads for a few seconds to lower the water pressure within the system.
    • Once the pressure drops low enough to trigger the automatic drain feature, the system will drain itself. 
  • Blow-out
    • Wear safety goggles the entire time, as this method can be dangerous.
    • Assemble the compressor and coupler needed for the blow-out process. 
    • Disconnect the sprinklers from the water supply or shut off the water source.
    • Use the coupler you prepared earlier to attach the air compressor to the sprinkler pipes. 
    • Turn on the sprinkler head farthest away from the compressor and close the backflow valves.
    • Gradually open the valve on the compressor and increase the pressure until you see water coming out of the sprinkler head you turned on. 
    • Turn off the sprinkler head when water stops coming out. 
    • Repeat for each sprinkler head. 
    • Disconnect the air compressor, release any remaining pent-up air pressure, and close all the valves. 

Note: Which method you should use will depend on your sprinkler system. Check with the installer or sprinkler manufacturer if you aren’t sure which method you should use.

11. Prepare flower beds and plants for winter

Your grass isn’t the only living thing in your landscape that needs a little help preparing for the freezing northern Illinois winter ahead. Your flower beds, bushes, and ornamental trees will benefit from protection measures you put in place in fall. 

Follow these simple steps to prepare your plant beds before the ground freezes:

  • Prune perennial plants (only those that prefer fall pruning)
  • Pull any weeds
  • Remove dead annual plants
  • Add soil amendments like compost and manure so they have time to enhance the soil before spring
  • Install an even thicker layer of mulch than usual to insulate roots and protect the soil from snow

Native plants are always more likely to survive a Chicago winter than non-natives. Consider using only natives when choosing plants for your landscape design. 

Fall lawn care means a healthier lawn next year

If you slack on fall lawn care, you’ll regret it in spring when you have a thin lawn plagued by pests and disease. With no preparation, you might not even have a living lawn after winter. 

The flip side is also true: If you take care of your lawn in fall, it’s far more likely to have a good spring next year, then a good summer, and so on. 

Even if our fall lawn care checklist seems like too much work for you, that’s no excuse to leave your lawn to fend for itself. You can free yourself from completing these chores without sacrificing your lawn’s health by hiring a lawn care professional with experience maintaining Chicago lawns. 

Main Photo Credit: Shane Adams | Flickr | CC BY 2.0

Jordan Ardoin

Jordan Ardoin is a writer and editor with a passion for sustainable, earth-friendly gardening and lawn care practices. When she isn't sharing her knowledge about lawn care and landscaping, you can find her curled up with a good book and a cat in her lap.