Lawn Care Guide for Big Horn County

Big Horn County, Wyoming

Data Story

About Lawn Care in Big Horn County, Wyoming

Tough Conditions in the Big Horn Basin

With a lawn difficulty score of 29.6, Big Horn County is one of the more challenging places in Wyoming to grow grass. This score sits well below the national median of 50.0, largely due to the desert-like precipitation levels in hardiness zone 5a.

High Heat and Desert Aridity

The county averages just 7.1 inches of rain annually, a fraction of the 30 inches needed for healthy lawns. While 41 extreme heat days push grass to its limits, the 2479 growing degree days offer enough warmth for growth if you can supply the necessary irrigation.

Foundational Prep is Essential

Comprehensive soil data is unavailable for this region, making a professional soil test your first step for success. Arid soils in the Basin are often alkaline, so focus on adding organic compost to improve water retention and balance the pH levels.

Managing 35 Weeks of Drought

The county experienced 35 weeks of drought over the past year, and the entire area remains abnormally dry. Effective water conservation involves mulching your lawn clippings to keep the soil surface cool and moist during those 41 scorching summer days.

Targeting Success in Zone 5a

Hardy cool-season grasses like Crested Wheatgrass are excellent choices for this climate's extreme dry spells. Aim to complete your seeding projects shortly after the last frost on May 9th to take advantage of the early summer growing window.

Lawn Difficulty Score

39/100
Moderate
Rainfall80/100
Soil Quality0/100
Temperature20/100
Growing Season40/100
Drought67/100

Soil Summary

pH

N/A

Texture

N/A

Drainage

N/A

Organic Matter

N/A

View full soil details

Recommended Grasses

Warm-SeasonTransition Zone

Buffalograss

Bouteloua dactyloides

Drought: 5/5Shade: 1/5
Suitability80%
View Seeds
Warm-SeasonTransition Zone

Blue Grama

Bouteloua gracilis

Drought: 5/5Shade: 1/5
Suitability80%
View Seeds
Cool-Season

Wheatgrass

Agropyron cristatum

Drought: 5/5Shade: 1/5
Suitability80%
View Seeds
Cool-SeasonTransition Zone

Tall Fescue

Festuca arundinacea

Drought: 4/5Shade: 3/5
Suitability76%
View Seeds

Climate Snapshot

Annual Precip

7.1"

Growing Degree Days

2,479.371

Base 50F

Last Spring Frost

05/09

First Fall Frost

09/29

Days Above 95F

41

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

3.2"

inches of water

Monthly Water

9,969

gallons

Estimated Monthly Cost

$79.75

at $0.008/gallon average

Estimates based on 7" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.

Common Lawn Problems in Big Horn County

Drought Stress

With only 7 inches of annual rainfall, lawns in Big Horn County face significant drought stress. Consider drought-tolerant grass species and deep, infrequent watering.

Persistent Drought Conditions

Big Horn County experienced drought conditions for 35 of the past 52 weeks. Prioritize water-efficient grasses and consider reducing lawn area.

Learn more about regional lawn challenges at The Lawn Report.

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

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.