LawnByCounty

Lawn Care Guide for Carroll County

Carroll County, Illinois

USDA SSURGO / PHZM

Data Story

About Lawn Care in Carroll County, Illinois

Carroll County's North-End Challenges

Carroll County has a lawn difficulty score of 67.0, making it slightly more work than the average Illinois lawn. Located in Zone 5a, it deals with some of the state's coldest winters and shortest growing windows. Success here depends on using hardy species that can survive deep freezes.

Cooler Climates and Steady Rainfall

Annual precipitation reaches 38.9 inches, while only 19 extreme heat days occur each year. The cooler climate, with 2,917 growing degree days, means your grass won't grow as aggressively as it would further south. This creates a shorter but more manageable mowing season for most homeowners.

High-Quality pH for Northern Turf

The soil pH of 6.39 is ideal for nutrient availability, supporting strong and healthy grass blades. The soil is a mix of 20.2% clay and 18.3% sand, which provides a good balance between moisture retention and drainage. These properties make the soil very responsive to standard lawn care treatments.

Long Drought Stretches in Carroll

Carroll County has struggled with 42 weeks of drought over the past year, indicating a persistent lack of moisture. While 100% of the county is abnormally dry, none of it currently falls into the severe category. Frequent monitoring of soil moisture is necessary to maintain lawn health during these long dry windows.

Wait for the Late May Frost

The final spring frost often holds off until May 2, so don't rush your spring planting too early. Fine fescues and Kentucky bluegrass are your best bets for the 5a hardiness zone. Plan to have your lawn established well before the first fall frost, which usually arrives by October 7.

Lawn Difficulty Score

18/100
Easy
Rainfall0/100
Soil Quality0/100
Temperature10/100
Growing Season40/100
Drought81/100

Soil Summary

pH

6.4

Texture

N/A

Drainage

N/A

Organic Matter

2.7%

View full soil details

Top Grass Fit for Carroll County

100/ 100

Excellent match

Jonathan Green Black Beauty Ultra

Jonathan Green

Top cultivar score: 100/100

USDA Zone Match100

Zone 5a vs Tall Fescue's 3–8 band.

Soil pH Fit100

Soil pH 6.39476267054351 vs Tall Fescue's 5.5–6.5 window.

Moisture Fit100

Precipitation 38.91" + soil AWC vs Tall Fescue's 20–30" need.

Establishment Window100

Growing-degree-days + frost window vs a intermediate-difficulty establishment.

If you spend any time on lawn care forums, Reddit's r/lawncare, or YouTube lawn channels, one name comes up more than any other: Jonathan Green Black Beauty Ultra. It's practically a cult favorite, and the label, cultivar story, and long-running owner reports explain why. The secret is in the genetics.
From The Lawn Report editorial review • rated 4.7/5
Shop Jonathan Green Black Beauty Ultra

In Carroll County, USDA zone 5a, soil pH 6.4, Jonathan Green Black Beauty Ultra scores 100/100 — a strong zone match, adequate moisture, and a long enough establishment window.

Why we ruled these out

  • Scotts Turf Builder BermudagrassUSDA zone 5a is below Scotts Turf Builder Bermudagrass's effective range (6–11); not recommended for this county.

See our fit-score methodology for how survivability is determined.

Recommended Grasses

Cool-Season

Kentucky Bluegrass

Poa pratensis

Drought: 2/5Shade: 2/5
Suitability70%
View Seeds
Cool-SeasonTransition Zone

Tall Fescue

Festuca arundinacea

Drought: 4/5Shade: 3/5
Suitability70%
View Seeds
Cool-Season

Perennial Ryegrass

Lolium perenne

Drought: 2/5Shade: 2/5
Suitability70%
View Seeds
Cool-Season

Fine Fescue

Festuca spp.

Drought: 3/5Shade: 5/5
Suitability70%
View Seeds

Best Grass Seed for Carroll County

Zone 5aCool-season grasses thrive here.

Find Seeds for Zone 5a

Climate Snapshot

Annual Precip

38.9"

Growing Degree Days

2,917.3

Base 50F

Last Spring Frost

05/02

First Fall Frost

10/07

Days Above 95F

19

Hardiness Zone

5a

Seeding Calendar — Zone 5A

J
F
M
A
M
J
J
A
S
O
N
D
Cool Seed (Best)
Cool Seed (OK)
Cool Seed (Best)
Cool Seed (OK)
Optimal (cool)
Acceptable (cool)
Optimal (warm)
Acceptable (warm)

Seasonal Lawn Care Checklist

Spring

  • Apply pre-emergent herbicide when soil reaches 55F
  • Overseed bare spots once frost risk passes
  • 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

  • Core aerate compacted areas
  • Apply fall fertilizer (highest N application for cool-season)
  • Continue mowing until growth stops
  • Rake or mulch leaves to prevent smothering

Winter

  • Avoid walking on frozen turf
  • Service mower and sharpen blades
  • Plan spring soil amendments based on fall test
  • Keep lawn clear of debris

Watering Deficit Calculator

50020,000 sq ft

Monthly Deficit

0.5"

inches of water

Monthly Water

1,687

gallons

Estimated Monthly Cost

$13.50

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 Carroll County

Persistent Drought Conditions

Carroll County experienced drought conditions for 42 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: Carroll County

Lawn Verdict

Carroll County sits in USDA hardiness zone 5a, a transitional zone where cool-season grasses dominate but some warm-season varieties can survive. with winter lows reaching around -20.0°F. and 2,917.3 growing degree days, sufficient for most common turfgrasses. Moderate rainfall (38.9 inches) generally supports healthy lawns with minimal supplemental watering.

Seasonal Breakdown

Wait until after May 2 to seed or overseed; soil temperatures should consistently reach 50-55°F. Cool summers (July averages 72.6°F) reduce heat stress — maintain regular mowing and moderate watering. Aerate and overseed cool-season lawns by early fall, well before October 7; this is the best renovation window. Cool winters (January averages 20.8°F) mean slow or dormant growth; keep debris off the lawn.

Watering Guidance

With 38.9 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. Cool summers reduce water demand; overwatering is a bigger risk than drought stress.

Regional Context

Carroll County is 4.3°F cooler than the Illinois average, USDA zone 5a helps guide grass selection compared to neighboring counties.

Want detailed soil composition, drainage classes, and soil series data? View soil details on SoilByCounty.com

Frequently Asked Questions

What USDA hardiness zone is Carroll County in?
Carroll County is located in USDA hardiness zone 5a, based on the 2023 USDA Plant Hardiness Zone Map. This zone helps determine which grass species are most likely to thrive in the county's climate.
What is the best grass for Carroll County?
Kentucky Bluegrass is the top recommendation for Carroll County, with a match score of 70/100. It grows best in zones 3a–7a and requires 30–40 inches of water annually.
How much rainfall does Carroll County get?
Carroll County receives an average of 38.9 inches of precipitation per year, based on NOAA 30-year climate normals. This provides adequate moisture for most lawn grasses with occasional supplemental watering during dry spells.
What is the soil pH in Carroll County?
The average soil pH in Carroll County is 6.4, based on USDA SSURGO data. This near-neutral pH supports most common lawn grasses with minimal soil amendment.

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.

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor