Lawn Care Guide for McDonough County
McDonough County, Illinois
USDA SSURGO / PHZMThis week in McDonough County · next up in about 4 weeks (Aug 26)
Get ready to seed cool-season grass — the best fall window is about to open.
Data Story
About Lawn Care in McDonough County, Illinois
Stable Growing Conditions in McDonough
McDonough County presents a favorable 70.5 lawn difficulty score, beating out the state average of 69.8. Residents in Hardiness Zone 6a find it easier to keep their lawns green compared to much of the country.
Moderate Heat and Steady Rain
With 38.8 inches of rain and only 26 extreme heat days, the local climate is generally gentle on turf. This lower-than-average heat count means less summer stress for cool-season grasses compared to southern Illinois counties.
Heavy Clay Requires Aeration Efforts
The 6.37 soil pH provides a welcoming environment for standard fertilizers and amendments. However, a low sand content of 7.4% means the soil relies heavily on its 22.9% clay composition, which can lead to slow drainage.
Persistent Drought Challenges Homeowners
Drought has been a persistent issue here, with 39 weeks of dry conditions over the last year. With nearly 93% of the county in severe drought, prioritize watering the most visible or valuable areas of your lawn to conserve water.
Planting Windows for Zone 6a
The window for spring seeding opens on April 17th, once the threat of frost has passed. Kentucky bluegrass and perennial ryegrass thrive here if they are well-rooted before the first fall frost on October 22nd.
Lawn Difficulty Score
Top Grass Fit for McDonough County
Excellent match
Outsidepride Midnight Kentucky Bluegrass Seed
Outsidepride
Top cultivar score: 100/100
Zone 6a vs Kentucky Bluegrass's 3–7 band.
Soil pH 6.37293045750548 vs Kentucky Bluegrass's 6–7 window.
Precipitation 38.79" + soil AWC vs Kentucky Bluegrass's 30–40" need.
Growing-degree-days + frost window vs a advanced-difficulty establishment.
Let's be direct: Outsidepride Midnight Kentucky Bluegrass is one of the best pure KBG seeds you can buy online, and it's not particularly close. Midnight is a specific cultivar — not a generic "Kentucky bluegrass blend" — and that distinction matters enormously.
In McDonough County, USDA zone 6a, soil pH 6.4, Outsidepride Midnight Kentucky Bluegrass Seed scores 100/100 — a strong zone match, adequate moisture, and a long enough establishment window.
Recommended Grasses
Tall Fescue
Festuca arundinacea
Choosing grass in McDonough County
Severe drought (39 wk in drought / yr) is the main thing shaping grass choice in McDonough County. Here's how to work with it — then the specific pick.
- Drought-tolerant grass seedWhat survives where water is scarce and often restricted.
- Kentucky Bluegrass, explainedTraits, care, and where Kentucky Bluegrass wins — the species behind your top match.
Top match for McDonough County: Kentucky Bluegrass
See the full breakdownPremium Grass Seeds is a sister site in our network. We may earn a commission from qualifying purchases made through its retailer links — this never affects your price. Guidance here reflects your county’s climate and soil data, not hands-on testing.
Climate Snapshot
Annual Precip
38.8"
Growing Degree Days
3,481.5
Base 50F
Last Spring Frost
04/17
First Fall Frost
10/22
Days Above 95F
26
Hardiness Zone
6a
Seeding Calendar — McDonough County
Personalized to this county’s frost dates — a 188-day growing season. Windows below are computed from local last-spring and first-fall frost normals, so they differ county-to-county even within USDA Zone 6A.
Plan your seeding — McDonough County
Pick a grass and a goal to get a personalized schedule anchored to this county’s frost dates.
- 1Prepare the seedbedAug 12 – Aug 25
Mow low, dethatch or rake, and loosen the top ½ inch of soil so seed makes good contact.
- 2Sow seedAug 26 – Sep 23
Best window to sow Kentucky Bluegrass in McDonough County, anchored to your local frost dates.
- 3EstablishSep 24 – Oct 21
Protect young seedlings: mow only after they reach ~3 inches and hold off on weed pre-emergents until established.
Silt retains moisture well — keep the seedbed consistently damp with about ¼ inch once daily, easing off if the surface stays wet to avoid damping-off.
Seasonal Lawn Care Checklist
Spring
- Apply pre-emergent herbicide when soil reaches 55F
- Begin mowing when grass reaches 3 inches
- Start irrigation if rainfall is below 1 inch/week
- Soil test every 2-3 years — adjust lime or sulfur as needed
Summer
- Mow at recommended height weekly
- Water deeply 1-2 times per week (1 inch total)
- Avoid fertilizing cool-season grasses in peak heat
- Scout for grubs and treat if >10 per sq ft
Fall
- Overseed warm-season lawns if thinning
- Apply fall fertilizer (highest N application for cool-season)
- Continue mowing until growth stops
- Rake or mulch leaves to prevent smothering
Winter
- Apply pre-emergent for winter weeds
- Service mower and sharpen blades
- Plan spring soil amendments based on fall test
- Keep lawn clear of debris
Watering Deficit Calculator
Monthly Deficit
0.6"
inches of water
Monthly Water
1,946
gallons
Estimated Monthly Cost
$15.56
at $0.008/gallon average
Estimates based on 39" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.
Common Lawn Problems in McDonough County
Persistent Drought Conditions
McDonough County experienced drought conditions for 39 of the past 52 weeks. Prioritize water-efficient grasses and consider reducing lawn area.
Learn more about regional lawn challenges at The Lawn Report.
Lawn Care Advisory: McDonough County
Lawn Verdict
McDonough County sits in USDA hardiness zone 6a, a transitional zone where cool-season grasses dominate but some warm-season varieties can survive. with winter lows reaching around -10.0°F. and 3,481.5 growing degree days, sufficient for most common turfgrasses. Moderate rainfall (38.8 inches) generally supports healthy lawns with minimal supplemental watering.
Seasonal Breakdown
Wait until after April 17 to seed or overseed; soil temperatures should consistently reach 50-55°F. Cool summers (July averages 75.1°F) reduce heat stress — maintain regular mowing and moderate watering. Aerate and overseed cool-season lawns by early fall, well before October 22; this is the best renovation window. Cool winters (January averages 24.4°F) mean slow or dormant growth; keep debris off the lawn.
Watering Guidance
With 38.8 inches of annual rainfall, established lawns typically need watering only during extended dry spells. Currently, 100.0% of the county is in moderate drought according to the US Drought Monitor. Consider reducing irrigation frequency and allowing cool-season lawns to go semi-dormant during peak heat. Standard warm-season watering of 1 inch per week is usually adequate during summer.
Regional Context
McDonough County is close to the Illinois average temperature, USDA zone 6a helps guide grass selection compared to neighboring counties.
Dig deeper into McDonough County
McDonough County is a USDA Zone 6A, silty-soil, cool-season county. Explore the data that shapes its lawn:
Want detailed soil composition, drainage classes, and soil series data? View soil details on SoilByCounty.com
Frequently Asked Questions
What USDA hardiness zone is McDonough County in?
What is the best grass for McDonough County?
How long is the growing season in McDonough County?
How much rainfall does McDonough County get?
What is the soil pH in McDonough County?
Data sourced from USDA SSURGO, NOAA Climate Normals (1991-2020), USDA Plant Hardiness Zone Map, and US Drought Monitor. Lawn difficulty scores and grass recommendations are estimates for informational purposes only.
Explore more data for McDonough County