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When to Plant Microgreens in Harrison 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.

Harrison County, Missouri is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 15, giving you a growing season of approximately 179 days.

At an elevation of 1,349 feet, Harrison County receives approximately 37.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Microgreens to ensure they mature before fall.

Harrison County, MO (Zone 5b) Moderate season
179 days
Last Spring Frost April 19
179 growing days
First Fall Frost October 15

Harrison County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (144 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: Apr 20 – May 18
Recommended (50%) ✓ Fits season (144 days to spare)
Start indoors: Mar 15 Transplant: Apr 19 🍅 Harvest: Apr 26 – May 24
Safe Start (90%) ✓ Fits season (146 days to spare)
Start indoors: Mar 29 Transplant: May 3 🍅 Harvest: May 10 – Jun 7

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 184 gal / 100 sq ft
Microgreens needs ~182 GDD — county provides 2,327 GDD Excellent fit

Microgreens Planting Timeline โ€” Harrison County, MO

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 15 Mar 15 โ€“ Mar 29
Transplant Outdoors April 19 Apr 19 โ€“ May 3
Direct Sow April 5 Apr 5 โ€“ Apr 26
Fall Sowing August 6 Aug 6 โ€“ Aug 20
Harvest April 26 Apr 26 โ€“ May 24

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 Transplant Outdoors Harvest
June โ€”
July โ€”
August Fall Sowing
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

7โ€“21 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

179 days

Growing Tips for Harrison County

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 Harrison County, MO?

Harrison County is in Zone 5b with an average last frost of April 19. Plan your Microgreens planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Harrison County, MO?

Harrison County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 15.

๐ŸŒฑ

Plan Your Garden with Confidence

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

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