LawnByCounty

Lawn Care Guide for Custer County

Custer County, South Dakota

USDA SSURGO / PHZM

Data Story

About Lawn Care in Custer County, South Dakota

Navigating Difficult High-Altitude Lawns

Custer County is the most challenging in this group, with a lawn difficulty score of just 36.6. Homeowners in this Zone 5a region must work significantly harder than the rest of the state to maintain a traditional lawn.

Short Seasons and High Evaporation

Though heat days are low at 14 per year, the 19.5 inches of annual rain is insufficient for most thirsty grass types. The 2,041 growing degree days reflect a shorter, cooler growth window that requires specialized plant choices.

Investigating Local Soil Secrets

Specific county-wide soil data is limited for Custer, making a home soil test kit an essential first step for any gardener. Knowing your specific yard's pH and drainage is the only way to overcome the county's low difficulty score.

Severe Drought Challenges in the Hills

Custer faces serious water stress, with 100% of the county abnormally dry and 28.6% in severe drought. After 35 weeks of drought in the last year, prioritizing drought-tolerant native grasses or xeriscaping is a smart long-term strategy.

A Brief Window for Custer Lawns

With the last frost occurring late on May 18 and the first fall frost on September 28, the growing window is tight. Focus on hardy, drought-resistant varieties and get them in the ground as soon as the spring soil warms to maximize growth.

Lawn Difficulty Score

36/100
Moderate
Rainfall80/100
Soil Quality0/100
Temperature7/100
Growing Season40/100
Drought67/100

Soil Summary

pH

N/A

Texture

N/A

Drainage

N/A

Organic Matter

N/A

View full soil details

Top Grass Fit for Custer County

Cool-season grasses are the general fit here

County soil and zone data are incomplete, so we show a category recommendation rather than a precise cultivar score for Custer County.

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

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

Best Grass Seed for Custer County

Zone 5aCool-season grasses thrive here.

Find Seeds for Zone 5a

Climate Snapshot

Annual Precip

19.5"

Growing Degree Days

2,041.475

Base 50F

Last Spring Frost

05/18

First Fall Frost

09/28

Days Above 95F

14

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

2.1"

inches of water

Monthly Water

6,419

gallons

Estimated Monthly Cost

$51.35

at $0.008/gallon average

Estimates based on 19" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.

Common Lawn Problems in Custer County

Drought Stress

With only 19 inches of annual rainfall, lawns in Custer County face significant drought stress. Consider drought-tolerant grass species and deep, infrequent watering.

Persistent Drought Conditions

Custer 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.

Lawn Care Advisory: Custer County

Lawn Verdict

Custer 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 2,041.475 growing degree days favor cool-season varieties like Kentucky bluegrass and fescue. Low rainfall (19.5 inches) means supplemental irrigation is essential during summer months.

Seasonal Breakdown

Wait until after May 18 to seed or overseed; soil temperatures should consistently reach 50-55°F. Cool summers (July averages 69.2°F) reduce heat stress — maintain regular mowing and moderate watering. Aerate and overseed cool-season lawns by early fall, well before September 28; this is the best renovation window. Cool winters (January averages 25.5°F) mean slow or dormant growth; keep debris off the lawn.

Watering Guidance

Low annual precipitation (19.5 inches) makes irrigation essential for maintaining green turf through summer. Currently, 100.0% of the county is in moderate drought according to the US Drought Monitor. Consider reducing irrigation frequency and allowing cool-season lawns to go semi-dormant during peak heat. Cool summers reduce water demand; overwatering is a bigger risk than drought stress.

Regional Context

Custer County is close to the South Dakota average temperature, it is somewhat drier than the state average, 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 Custer County in?
Custer 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 Custer County?
Buffalograss is the top recommendation for Custer County, with a match score of 80/100. It grows best in zones 5a–8a and requires 10–20 inches of water annually.
How much rainfall does Custer County get?
Custer County receives an average of 19.5 inches of precipitation per year, based on NOAA 30-year climate normals. This relatively low rainfall makes drought-tolerant grass species particularly important.

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