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When to Plant Microgreens in Clark County, MO

Microgreens are young seedlings of vegetables and herbs harvested at the cotyledon or first true leaf stage. They pack concentrated flavors and nutrients in a tiny package.

Clark County, Missouri is in USDA Zone 5b. The average last spring frost is April 16 and the first fall frost is October 18, giving you a growing season of approximately 185 days.

At an elevation of 833 feet, Clark County receives approximately 33 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Microgreens during the growing season.

Clark County, MO (Zone 5b) Moderate season
185 days
Last Spring Frost April 16
185 growing days
First Fall Frost October 18

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (150 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: Apr 17 – May 15
Recommended (50%) ✓ Fits season (150 days to spare)
Start indoors: Mar 12 Transplant: Apr 16 🍅 Harvest: Apr 23 – May 21
Safe Start (90%) ✓ Fits season (146 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: May 9 – Jun 6

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Clark County

How your county's soil matches Microgreens's growing requirements.

Soil pH

Your soil pH (5.6โ€“6.6) overlaps with Microgreens's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Clark County is excellent for Microgreens โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Microgreens.

How to Plant Microgreens

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Microgreens

36
successive plantings in your 185-day season

Sow every 0.7 weeks. Last sowing by Sep 27 to harvest before frost.

For a dedicated fall crop, sow by Aug 09.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 413 gal / 100 sq ft
Microgreens needs ~214 GDD — county provides 2,821 GDD Excellent fit

Microgreens Planting Timeline โ€” Clark County, MO

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 12 Mar 12 โ€“ Mar 26
Transplant Outdoors April 16 Apr 16 โ€“ Apr 30
Direct Sow April 2 Apr 2 โ€“ Apr 23
Fall Sowing August 9 Aug 9 โ€“ Aug 23
Harvest April 23 Apr 23 โ€“ May 21

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Transplant Outdoors Direct Sow Harvest
May Harvest
June โ€”
July โ€”
August Fall Sowing
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

7โ€“21 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

185 days in Clark County

Growing Tips for Microgreens in Clark County

Direct sow Microgreens outdoors after April 16 in Clark County when soil has warmed and frost danger has passed.

Your generous 185.0-day season in Clark County allows multiple plantings of Microgreens. Sow every 3.0 days for continuous harvest.

General growing tips

Sow seeds densely on shallow trays of moist growing medium. Cover until germination, then provide light. Harvest with scissors when 1-3 inches tall. Grow year-round indoors.

Frequently Asked Questions

When should I plant Microgreens in Clark County, MO?

Clark County is in Zone 5b with an average last frost of April 16. Plan your Microgreens planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clark County, MO?

Clark County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 16 and first fall frost is October 18.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clark County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Clark County, MO. Local conditions may vary. Last updated: April 2026.