Lawn Care Guide for Audubon County
Audubon County, Iowa
USDA SSURGO / PHZMThis week in Audubon County · next up in 10 days (Aug 7)
Get ready to seed cool-season grass — the best fall window is about to open.
Data Story
About Lawn Care in Audubon County, Iowa
Audubon County's Reliable Growing Environment
Audubon County matches the state's hospitable growing conditions with a lawn difficulty score of 76.5. Situated in Zone 5a, the climate supports traditional cool-season lawns with a manageable level of effort. It remains significantly easier than the national median, offering a friendly landscape for beginners and experts alike.
Temperate Summers with Moderate Rain
With 35.0 inches of annual precipitation, the county is slightly drier than the state average of 36.1 inches. However, only 11 extreme heat days occur per year, which is significantly better than the state average of 16. This moderate heat helps grass survive on less water during the peak of the 2,779 growing degree day season.
Ideal Drainage in Silty Clay Loam
The county features silty clay loam soil that is classified as well-drained, a major advantage for healthy root systems. While the clay content is 29.4%, the structure allows water to move efficiently compared to heavier soils. A pH of 6.19 is near the sweet spot for nutrient availability, though it leans slightly toward the acidic side.
Resilient Against Prolonged Dryness
Only 7 weeks of drought were recorded over the past year, and current conditions show only 0.4% of the county is abnormally dry. This makes Audubon much more resilient than its southern neighbors. The well-drained soil and low frequency of drought mean that standard rain and occasional watering are usually sufficient.
Plan Around the Late Spring Frost
Kentucky Bluegrass blends perform exceptionally well in Audubon’s well-drained loamy soils. The typical growing window runs from the last spring frost on May 2 to the first fall frost on October 3. Aim to finish any major seeding by mid-September to ensure the silty clay loam settles before the first freeze.
Lawn Difficulty Score
Top Grass Fit for Audubon County
Excellent match
Jonathan Green Black Beauty Ultra
Jonathan Green
Top cultivar score: 100/100
Zone 5a vs Tall Fescue's 3–8 band.
Soil pH 6.18964947887303 vs Tall Fescue's 5.5–6.5 window.
Precipitation 35.03" + soil AWC vs Tall Fescue's 20–30" need.
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.
In Audubon County, USDA zone 5a, soil pH 6.2, silty clay loam, 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 Bermudagrass — USDA 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
Tall Fescue
Festuca arundinacea
Choosing grass in Audubon County
Your loamy soil and cool-season conditions narrow the field fast. Here's how to think it through for Audubon County — then the specific pick.
- Best cool-season grass seed for fallYour prime seeding window and the top cool-season picks.
- How grass cultivars get scored (NTEP)The independent trial data behind every species ranking.
- Tall Fescue, explainedTraits, care, and where Tall Fescue wins — the species behind your top match.
Top match for Audubon County: Tall Fescue
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
35.0"
Growing Degree Days
2,778.7
Base 50F
Last Spring Frost
05/02
First Fall Frost
10/03
Days Above 95F
11
Hardiness Zone
5a
Seeding Calendar — Audubon County
Personalized to this county’s frost dates — a 154-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.
Plan your seeding — Audubon County
Pick a grass and a goal to get a personalized schedule anchored to this county’s frost dates.
- 1Prepare the seedbedJul 24 – Aug 6
Mow low, dethatch or rake, and loosen the top ½ inch of soil so seed makes good contact.
- 2Sow seedAug 7 – Sep 4
Best window to sow Kentucky Bluegrass in Audubon County, anchored to your local frost dates.
- 3EstablishSep 5 – Oct 2
Protect young seedlings: mow only after they reach ~3 inches and hold off on weed pre-emergents until established.
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
Monthly Deficit
0.9"
inches of water
Monthly Water
2,649
gallons
Estimated Monthly Cost
$21.19
at $0.008/gallon average
Estimates based on 35" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.
Lawn Care Advisory: Audubon County
Lawn Verdict
Audubon 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 2,778.7 growing degree days, sufficient for most common turfgrasses. Moderate rainfall (35.0 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 72.1°F) reduce heat stress — maintain regular mowing and moderate watering. Aerate and overseed cool-season lawns by early fall, well before October 3; this is the best renovation window. Winters are harsh (January averages 18.4°F); avoid foot traffic on frozen turf and plan snow mold prevention.
Watering Guidance
With 35.0 inches of annual rainfall, established lawns typically need watering only during extended dry spells. Currently, 0.4% 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
Audubon County is close to the Iowa average temperature, USDA zone 5a helps guide grass selection compared to neighboring counties.
Dig deeper into Audubon County
Audubon 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 Audubon County in?
What is the best grass for Audubon County?
How long is the growing season in Audubon County?
How much rainfall does Audubon County get?
What is the soil pH in Audubon 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 Audubon County