Lawn Care Guide for St. Francois County
St. Francois County, Missouri
USDA SSURGO / PHZMThis week in St. Francois County · next up in about 4 weeks (Aug 25)
Get ready to seed cool-season grass — the best fall window is about to open.
Data Story
About Lawn Care in St. Francois County, Missouri
Managing Mid-Range Lawn Difficulty
With a score of 56.5, St. Francois County is more challenging for lawn care than the state average. This Zone 6b area requires proactive maintenance to stay healthy compared to the broader Missouri landscape.
Plenty of Rain for Thirsty Turf
The county receives 45.2 inches of precipitation annually, which is higher than the state average of 43.7. This extra moisture helps offset the 32 extreme heat days, keeping grass greener for longer into the summer months.
Correcting Low Soil pH
The soil pH of 5.69 is quite acidic and typically requires lime amendments to reach the ideal 6.0-7.0 range. On the plus side, the silty clay loam is well-drained, which prevents water from pooling around the roots of your grass.
Targeted Watering for Dry Zones
While most of the county is abnormally dry, 0.4% is already facing severe drought conditions. Target these vulnerable spots with consistent irrigation to mitigate the effects of the 28 weeks of drought seen last year.
Spring Seeding for Best Results
Target the window after April 13 to begin seeding your lawn with cool-season grasses like Perennial Ryegrass. You have 4,114 growing degree days to work with before the first frost hits around October 21.
Lawn Difficulty Score
Soil Summary
pH
5.7
Texture
Silty clay loam
Drainage
Well drained
Organic Matter
15.6%
Top Grass Fit for St. Francois County
Excellent match
Jonathan Green Black Beauty Ultra
Jonathan Green
Top cultivar score: 100/100
Zone 6b vs Tall Fescue's 3–8 band.
Soil pH 5.68597225471269 vs Tall Fescue's 5.5–6.5 window.
Precipitation 45.16" + 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 St. Francois County, USDA zone 6b, soil pH 5.7, silty clay loam, Jonathan Green Black Beauty Ultra scores 100/100 — a strong zone match, adequate moisture, and a long enough establishment window.
Recommended Grasses
Tall Fescue
Festuca arundinacea
Choosing grass in St. Francois County
Severe drought (28 wk in drought / yr) is the main thing shaping grass choice in St. Francois County. Here's how to work with it — then the specific pick.
- Drought-tolerant grass seedWhat survives where water is scarce and often restricted.
- Tall Fescue, explainedTraits, care, and where Tall Fescue wins — the species behind your top match.
Top match for St. Francois 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
45.2"
Growing Degree Days
4,114.3
Base 50F
Last Spring Frost
04/13
First Fall Frost
10/21
Days Above 95F
32
Hardiness Zone
6b
Seeding Calendar — St. Francois County
Personalized to this county’s frost dates — a 191-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 6B.
Plan your seeding — St. Francois County
Pick a grass and a goal to get a personalized schedule anchored to this county’s frost dates.
- 1Prepare the seedbedAug 11 – Aug 24
Mow low, dethatch or rake, and loosen the top ½ inch of soil so seed makes good contact.
- 2Sow seedAug 25 – Sep 22
Best window to sow Tall Fescue in St. Francois County, anchored to your local frost dates.
- 3EstablishSep 23 – Oct 20
Protect young seedlings: mow only after they reach ~3 inches and hold off on weed pre-emergents until established.
Silt retains moisture well — keep the seedbed consistently damp with about ¼ inch once daily, easing off if the surface stays wet to avoid damping-off.
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
- 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
- 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
- Keep lawn clear of debris
Watering Deficit Calculator
Monthly Deficit
0.2"
inches of water
Monthly Water
528
gallons
Estimated Monthly Cost
$4.23
at $0.008/gallon average
Estimates based on 45" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.
Common Lawn Problems in St. Francois County
Persistent Drought Conditions
St. Francois County experienced drought conditions for 28 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: St. Francois County
Lawn Verdict
St. Francois County sits in USDA hardiness zone 6b, a transitional zone where cool-season grasses dominate but some warm-season varieties can survive. with winter lows reaching around -5.0°F. and 4,114.3 growing degree days annually, supporting vigorous warm-season lawns. Moderate rainfall (45.2 inches) generally supports healthy lawns with minimal supplemental watering.
Seasonal Breakdown
Wait until after April 13 to seed or overseed; soil temperatures should consistently reach 50-55°F. Cool summers (July averages 77.7°F) reduce heat stress — maintain regular mowing and moderate watering. With 31.5 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 October 21; this is the best renovation window. Cool winters (January averages 32.7°F) mean slow or dormant growth; keep debris off the lawn.
Watering Guidance
With 45.2 inches of annual rainfall, established lawns typically need watering only during extended dry spells. Currently, 100.0% of the county is in abnormally dry according to the US Drought Monitor. Standard warm-season watering of 1 inch per week is usually adequate during summer.
Regional Context
St. Francois County is close to the Missouri average temperature, USDA zone 6b helps guide grass selection compared to neighboring counties.
Dig deeper into St. Francois County
St. Francois County is a USDA Zone 6B, silty-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 St. Francois County in?
What is the best grass for St. Francois County?
How long is the growing season in St. Francois County?
How much rainfall does St. Francois County get?
What is the soil pH in St. Francois 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 St. Francois County