LawnByCounty

Lawn Care Guide for Worth County

Worth County, Iowa

USDA SSURGO / PHZM

This week in Worth County · next up in about 2 weeks (Aug 8)

Get ready to seed cool-season grass — the best fall window is about to open.

Data Story

About Lawn Care in Worth County, Iowa

An Ideal Environment for Iowa Lawns

Worth County is a standout for easy lawn care, scoring a 78.8 on the difficulty scale. This score exceeds both the national median of 50.0 and the Iowa state average of 77.2. Situated in Hardiness Zone 5a, the county provides a very hospitable climate for lush, green turf.

Mild Summers and Sufficient Rainfall

Lawns benefit from 35.5 inches of annual precipitation, which aligns closely with the state average of 36.1 inches. Extreme heat is rare here, with only 4 days per year hitting 90°F compared to the 16-day state average. This lack of heat stress means your grass stays greener longer into the summer months.

Thriving in Silt Loam Soils

The soil features a silt loam texture with a 36.5% sand content, providing a lighter structure than heavier clay regions. With a pH of 6.45, the ground is naturally optimized for grass health without the need for heavy lime applications. Because the soil is somewhat poorly drained, homeowners should ensure proper grading to avoid standing water.

High Resilience to Dry Weather

Worth County shows strong drought resilience, recording only 7 weeks of drought over the last year. Currently, only 31.7% of the area faces abnormally dry conditions, which is significantly better than many neighboring counties. Natural rainfall handles most of the work here, keeping irrigation costs low.

Start Planting After Early May

Fine fescues and perennial ryegrass thrive in this northern Iowa climate and soil type. Plan your primary seeding for after the last spring frost on May 4 to ensure survival. A second window for overseeding opens in late August, well before the first fall frost on October 4.

Lawn Difficulty Score

14/100
Easy
Rainfall0/100
Soil Quality25/100
Temperature2/100
Growing Season30/100
Drought13/100

Soil Summary

pH

6.5

Texture

Silt loam

Drainage

Somewhat poorly drained

Organic Matter

6.0%

View full soil details

Top Grass Fit for Worth County

100/ 100

Excellent match

Pennington Smart Seed Sun & Shade

Pennington

Top cultivar score: 100/100

Estimated — county soil data incomplete.

USDA Zone Match100

Zone 5a vs Tall Fescue's 3–8 band.

Soil pH Fit100

Soil pH 6.45318215721392 vs Tall Fescue's 5.5–6.5 window.

Moisture Fit100

Precipitation 35.47" + soil AWC vs Tall Fescue's 20–30" need.

Establishment Window100

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

Pennington Smart Seed Sun & Shade is the best value in the cool-season grass seed market. Period. You get a quality fescue/KBG blend with genuine drought tolerance coating at a price point significantly below premium options like BBU or Barenbrug RTF.
From The Lawn Report editorial review • rated 4.4/5
Shop Pennington Smart Seed Sun & Shade

In Worth County, USDA zone 5a, soil pH 6.5, silt loam, Pennington Smart Seed Sun & Shade 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

Choosing grass in Worth County

Poor drainage (Somewhat poorly drained) is the main thing shaping grass choice in Worth County. Here's how to work with it — then the specific pick.

Top match for Worth County: Tall Fescue

See the full breakdown

Premium 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

35.5"

Growing Degree Days

2,224.5

Base 50F

Last Spring Frost

05/04

First Fall Frost

10/04

Days Above 95F

4

Hardiness Zone

5a

Seeding Calendar — Worth County

Personalized to this county’s frost dates — a 153-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 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)
Cool-season seeding (best)Aug 8Sep 5
Cool-season seeding (spring)Apr 26May 31
Core aerationAug 8Sep 5
Spring pre-emergentApr 12May 3

Plan your seeding — Worth County

Pick a grass and a goal to get a personalized schedule anchored to this county’s frost dates.

Goal
  1. 1
    Prepare the seedbedJul 25 – Aug 7

    Mow low, dethatch or rake, and loosen the top ½ inch of soil so seed makes good contact.

  2. 2
    Sow seedAug 8 – Sep 5

    Best window to sow Kentucky Bluegrass in Worth County, anchored to your local frost dates.

  3. 3
    EstablishSep 6 – Oct 3

    Protect young seedlings: mow only after they reach ~3 inches and hold off on weed pre-emergents until established.

Watering while it germinatesLoam soil

Loam holds moisture evenly — water about ¼ inch once or twice daily to keep the top inch of the seedbed consistently moist until germination.

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

0.7"

inches of water

Monthly Water

2,253

gallons

Estimated Monthly Cost

$18.03

at $0.008/gallon average

Estimates based on 35" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.

Lawn Care Advisory: Worth County

Lawn Verdict

Worth 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. though only 2,224.5 growing degree days favor cool-season varieties like Kentucky bluegrass and fescue. Moderate rainfall (35.5 inches) generally supports healthy lawns with minimal supplemental watering.

Seasonal Breakdown

Wait until after May 4 to seed or overseed; soil temperatures should consistently reach 50-55°F. Cool summers (July averages 69.0°F) reduce heat stress — maintain regular mowing and moderate watering. Aerate and overseed cool-season lawns by early fall, well before October 4; this is the best renovation window. Winters are harsh (January averages 12.6°F); avoid foot traffic on frozen turf and plan snow mold prevention.

Watering Guidance

With 35.5 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

Worth County is 5.0°F cooler than the Iowa average, the growing season is noticeably shorter than the state average, USDA zone 5a helps guide grass selection compared to neighboring counties.

Dig deeper into Worth County

Worth County is a USDA Zone 5A, loamy-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 Worth County in?
Worth 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 Worth County?
Kentucky Bluegrass is the top recommendation for Worth County, with a match score of 70/100. It grows best in zones 3a–7a and requires 30–40 inches of water annually.
How long is the growing season in Worth County?
Worth County has a growing season of approximately 153 days, based on NOAA 30-year climate normals (1991–2020). This is calculated from the average last spring frost to the average first fall frost.
How much rainfall does Worth County get?
Worth County receives an average of 35.5 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 Worth County?
The average soil pH in Worth County is 6.5, 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