LawnByCounty

Lawn Care Guide for Tama County

Tama County, Iowa

USDA SSURGO / PHZM

Data Story

About Lawn Care in Tama County, Iowa

Ideal Turf Conditions in Tama County

Tama County earns a high lawn difficulty score of 80.5, placing it well above both state and national averages for ease of maintenance. The 5a hardiness zone is standard for the region, supporting a wide variety of durable cool-season grasses. Homeowners can expect consistent results with standard lawn care practices.

Plenty of Rain and Mild Heat

The county receives a robust 37.1 inches of precipitation annually, which is higher than the state average of 36.1. Only 12 extreme heat days occur per year, the lowest in this group, protecting grass from burning out in the summer. This combination of high moisture and low heat stress is perfect for keeping lawns green longer.

Well-Drained Loam Foundations

Lawns in Tama County benefit from moderately well-drained loam soil and a healthy pH of 6.30. The soil composition of 23.1% clay and 17.7% sand prevents waterlogging while still holding enough moisture for the roots. This balanced structure is generally easy to work with and supports vigorous root development.

Minor Dry Spells Are Manageable

With only 6 weeks of drought in the past year and only 5.0% of the area currently abnormally dry, water stress is low. The county has avoided the more severe drought conditions seen elsewhere in Iowa recently. Standard irrigation during the occasional dry week is usually sufficient to maintain turf health.

April to October Growing Window

The last spring frost on April 30 signals the start of the primary growing season for this 5a zone. With the first fall frost arriving on October 9, you have a solid five-month window for active maintenance and growth. Kentucky Bluegrass is a traditional favorite here that responds well to the ample local rainfall.

Lawn Difficulty Score

10/100
Easy
Rainfall0/100
Soil Quality0/100
Temperature6/100
Growing Season40/100
Drought12/100

Soil Summary

pH

6.3

Texture

Loam

Drainage

Moderately well drained

Organic Matter

2.5%

View full soil details

Top Grass Fit for Tama 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 6.30150425114454 vs Tall Fescue's 5.5–6.5 window.

Moisture Fit100

Precipitation 37.07666666666667" + 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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In Tama County, USDA zone 5a, soil pH 6.3, 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 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 Tama County

Zone 5aCool-season grasses thrive here.

Find Seeds for Zone 5a

Climate Snapshot

Annual Precip

37.1"

Growing Degree Days

2,848.7

Base 50F

Last Spring Frost

04/30

First Fall Frost

10/09

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

0.7"

inches of water

Monthly Water

2,154

gallons

Estimated Monthly Cost

$17.23

at $0.008/gallon average

Estimates based on 37" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.

Lawn Care Advisory: Tama County

Lawn Verdict

Tama 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 2,848.7 growing degree days, sufficient for most common turfgrasses. Moderate rainfall (37.1 inches) generally supports healthy lawns with minimal supplemental watering.

Seasonal Breakdown

Wait until after April 30 to seed or overseed; soil temperatures should consistently reach 50-55°F. Cool summers (July averages 72.5°F) reduce heat stress — maintain regular mowing and moderate watering. Aerate and overseed cool-season lawns by early fall, well before October 9; this is the best renovation window. Winters are harsh (January averages 18.1°F); avoid foot traffic on frozen turf and plan snow mold prevention.

Watering Guidance

With 37.1 inches of annual rainfall, established lawns typically need watering only during extended dry spells. Currently, 5.0% 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

Tama 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 Tama County in?
Tama 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 Tama County?
Kentucky Bluegrass is the top recommendation for Tama 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 Tama County get?
Tama County receives an average of 37.1 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 Tama County?
The average soil pH in Tama County is 6.3, 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