LawnByCounty

Lawn Care Guide for Dubuque County

Dubuque County, Iowa

USDA SSURGO / PHZM

Data Story

About Lawn Care in Dubuque County, Iowa

Sandy Terrain in Dubuque

Dubuque County scores a 72.0 on the difficulty scale, making it slightly tougher than the state average but much easier than the national norm. Homeowners in this Zone 5a region must account for unique soil drainage and significant drought history.

Consistent Rain and Mild Heat

The county sees 38.8 inches of rain annually, well above the state average, and faces only 12 extreme heat days. These moderate temperatures and 2906 growing degree days create a pleasant environment for cool-season grasses to stay green.

Fast-Draining Loamy Fine Sand

Unlike most of Iowa, Dubuque features excessively drained loamy fine sand. While the 6.38 pH is ideal, the sandy texture means the soil does not hold water well, so your lawn may require more frequent watering than neighbors to the west.

Recovering from Significant Drought

With 31 weeks of drought over the past year, Dubuque has been the hardest hit in this group. Since 100% of the area is still abnormally dry, homeowners should use organic compost to improve the water-holding capacity of the sandy soil.

Target the Late April Window

Plan to seed after the last frost on April 28 to give your lawn a strong start. Because the sand drains quickly, ensure consistent moisture during the establishment phase before the first fall frost on October 11.

Lawn Difficulty Score

15/100
Easy
Rainfall0/100
Soil Quality0/100
Temperature6/100
Growing Season40/100
Drought60/100

Soil Summary

pH

6.4

Texture

Loamy fine sand

Drainage

Excessively drained

Organic Matter

2.5%

View full soil details

Top Grass Fit for Dubuque 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 6.38054892153221 vs Tall Fescue's 5.5–6.5 window.

Moisture Fit100

Precipitation 38.78" + soil AWC vs Tall Fescue's 20–30" need.

Establishment Window100

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

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From The Lawn Report editorial review • rated 4.7/5
Shop Jonathan Green Black Beauty Ultra

In Dubuque County, USDA zone 5a, soil pH 6.4, loamy fine sand, 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 Dubuque County

Zone 5aCool-season grasses thrive here.

Find Seeds for Zone 5a

Climate Snapshot

Annual Precip

38.8"

Growing Degree Days

2,905.567

Base 50F

Last Spring Frost

04/28

First Fall Frost

10/11

Days Above 95F

12

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

0.6"

inches of water

Monthly Water

1,751

gallons

Estimated Monthly Cost

$14.01

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 Dubuque County

Persistent Drought Conditions

Dubuque County experienced drought conditions for 31 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: Dubuque County

Lawn Verdict

Dubuque 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 2,905.567 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 28 to seed or overseed; soil temperatures should consistently reach 50-55°F. Cool summers (July averages 72.9°F) reduce heat stress — maintain regular mowing and moderate watering. Aerate and overseed cool-season lawns by early fall, well before October 11; this is the best renovation window. Winters are harsh (January averages 19.0°F); avoid foot traffic on frozen turf and plan snow mold prevention.

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 abnormally dry according to the US Drought Monitor. Cool summers reduce water demand; overwatering is a bigger risk than drought stress.

Regional Context

Dubuque County is close to the Iowa average temperature, 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 Dubuque County in?
Dubuque 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 Dubuque County?
Kentucky Bluegrass is the top recommendation for Dubuque 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 Dubuque County get?
Dubuque County receives an average of 38.8 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 Dubuque County?
The average soil pH in Dubuque 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