LawnByCounty

Lawn Care Guide for Union County

Union County, Arkansas

USDA SSURGO / PHZM

Data Story

About Lawn Care in Union County, Arkansas

Significant Lawn Challenges in Union County

Union County is one of the most difficult places for lawns, with a very low difficulty score of 23.1. This is far more challenging than the state average of 37.3 and the national median of 50.0. Success in Zone 8b requires an expert focus on heat and soil acidity.

Extreme Summer Heat and High Rain

With 82 extreme heat days, Union County is much hotter than the state average of 64 days. It also receives 52.8 inches of rain annually, which exceeds the ideal range for many turfgrasses. These conditions create high stress for cool-season grasses, making warm-season varieties mandatory.

Managing Highly Acidic, Sandy Soils

The soil is extremely acidic with a pH of 5.10, requiring significant lime treatment to reach the 6.0-7.0 ideal. With 55.4% sand, the soil drains rapidly and may struggle to hold onto essential nutrients. Frequent, light fertilization and watering are necessary to keep grass fed and hydrated.

Conserving Water Amidst Frequent Drought

The county spent 27 weeks in drought over the last year, and over 40% of the area currently faces severe drought. Because sandy soils lose moisture quickly, you must monitor your lawn daily during the hot summer months. Using rain barrels can provide a helpful supplemental water source during these periods.

Heat-Loving Grasses for Union County

Bermudagrass and St. Augustine are the most resilient choices for the intense heat of Zone 8b. You can start your lawn as early as late March, following the typical last frost on March 24th. Given the low difficulty score, don't be afraid to consult a local extension for a custom soil plan.

Lawn Difficulty Score

30/100
Easy
Rainfall16/100
Soil Quality20/100
Temperature41/100
Growing Season40/100
Drought52/100

Soil Summary

pH

5.1

Texture

N/A

Drainage

N/A

Organic Matter

1.7%

View full soil details

Top Grass Fit for Union County

92/ 100

Excellent match

Jonathan Green Black Beauty Ultra

Jonathan Green

Top cultivar score: 92/100

USDA Zone Match100

Zone 8b vs Tall Fescue's 3–8 band.

Soil pH Fit60

Soil pH 5.10490410973522 vs Tall Fescue's 5.5–6.5 window.

Moisture Fit100

Precipitation 52.78" + soil AWC vs Tall Fescue's 20–30" need.

Establishment Window100

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.
From The Lawn Report editorial review • rated 4.7/5
Shop Jonathan Green Black Beauty Ultra

In Union County, USDA zone 8b, soil pH 5.1, Jonathan Green Black Beauty Ultra scores 92/100 — a strong zone match, adequate moisture, and a long enough establishment window.

Recommended Grasses

Warm-Season

Centipedegrass

Eremochloa ophiuroides

Drought: 3/5Shade: 3/5
Suitability70%
View Seeds
Cool-SeasonTransition Zone

Tall Fescue

Festuca arundinacea

Drought: 4/5Shade: 3/5
Suitability55%
View Seeds
Warm-SeasonTransition Zone

Bermudagrass

Cynodon dactylon

Drought: 5/5Shade: 1/5
Suitability55%
View Seeds
Warm-SeasonTransition Zone

Zoysiagrass

Zoysia japonica

Drought: 4/5Shade: 3/5
Suitability55%
View Seeds

Best Grass Seed for Union County

Zone 8bCool- and warm-season grasses thrive here.

Find Seeds for Zone 8b

Climate Snapshot

Annual Precip

52.8"

Growing Degree Days

5,716.75

Base 50F

Last Spring Frost

03/24

First Fall Frost

11/07

Days Above 95F

82

Hardiness Zone

8b

Seeding Calendar — Zone 8B

J
F
M
A
M
J
J
A
S
O
N
D
Cool Seed (Best)
Cool Seed (OK)
Warm Seed (Best)
Warm Seed (OK)
Cool Seed (Best)
Cool Seed (OK)
Warm Seed (Best)
Warm Seed (OK)
Optimal (cool)
Acceptable (cool)
Optimal (warm)
Acceptable (warm)

Seasonal Lawn Care Checklist

Spring

  • Apply pre-emergent herbicide when soil reaches 55F
  • Begin mowing when grass reaches 3 inches
  • Start irrigation if rainfall is below 1 inch/week
  • Soil test every 2-3 years — adjust lime or sulfur as needed

Summer

  • Raise mowing height to reduce heat stress
  • 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

  • Overseed warm-season lawns if thinning
  • Apply fall fertilizer (highest N application for cool-season)
  • Continue mowing until growth stops
  • Rake or mulch leaves to prevent smothering

Winter

  • Apply pre-emergent for winter weeds
  • Service mower and sharpen blades
  • Plan spring soil amendments based on fall test
  • Overseed with ryegrass for winter color

Watering Deficit Calculator

50020,000 sq ft

Monthly Deficit

0.0"

inches of water

Monthly Water

0

gallons

Estimated Monthly Cost

$0.00

at $0.008/gallon average

Estimates based on 53" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.

Common Lawn Problems in Union County

Excess Moisture & Fungal Disease

High annual rainfall (53 inches) increases risk of fungal diseases like brown patch and dollar spot. Ensure good drainage and avoid overwatering.

Acidic Soil

Soil pH of 5.1 is below the ideal range for most grasses (6.0-7.0). Apply agricultural lime to raise pH gradually.

Persistent Drought Conditions

Union County experienced drought conditions for 27 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: Union County

Lawn Verdict

Union County falls in USDA hardiness zone 8b, a favorable range for both cool- and warm-season grasses. with winter lows reaching around 15.0°F. and 5,716.75 growing degree days annually, supporting vigorous warm-season lawns. High annual precipitation (52.8 inches) supports lush growth but increases disease pressure.

Seasonal Breakdown

Wait until after March 24 to seed or overseed; soil temperatures should consistently reach 50-55°F. Summers are warm (July averages 82.1°F); monitor for heat stress and water when soil is dry 2-3 inches down. With 82.05000000000001 days above 90°F annually, warm-season grasses recover faster from summer stress than cool-season types. Aerate and overseed cool-season lawns by early fall, well before November 7; this is the best renovation window. Mild winters (January averages 44.1°F) allow year-round mowing for warm-season lawns and minimal dormancy.

Watering Guidance

Union County receives abundant rainfall (52.8 inches annually), so lawns rarely need supplemental irrigation. 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. Standard warm-season watering of 1 inch per week is usually adequate during summer. High heat accumulation means warm-season grasses use water aggressively — monitor soil moisture regularly.

Regional Context

Union County is close to the Arkansas average temperature, USDA zone 8b 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 Union County in?
Union County is located in USDA hardiness zone 8b, 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 Union County?
Centipedegrass is the top recommendation for Union County, with a match score of 70/100. It grows best in zones 7b–9a and requires 20–30 inches of water annually.
How much rainfall does Union County get?
Union County receives an average of 52.8 inches of precipitation per year, based on NOAA 30-year climate normals. This abundant rainfall supports a wide range of grass species with minimal supplemental irrigation.
What is the soil pH in Union County?
The average soil pH in Union County is 5.1, based on USDA SSURGO data. This acidic soil may benefit from lime application to raise pH for optimal grass growth.

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