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When to Plant Microgreens in Clay 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.

Clay County, Missouri is in USDA Zone 6a. The average last spring frost is April 13 and the first fall frost is October 24, giving you a growing season of approximately 194 days.

At an elevation of 1,373 feet, Clay County receives approximately 33.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Microgreens during the growing season.

Clay County, MO (Zone 6a) Moderate season
194 days
Last Spring Frost April 13
194 growing days
First Fall Frost October 24

Clay County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (157 days to spare)
Start indoors: Mar 2 Transplant: Apr 6 🍅 Harvest: Apr 13 – May 11
Recommended (50%) ✓ Fits season (159 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: Apr 20 – May 18
Safe Start (90%) ✓ Fits season (156 days to spare)
Start indoors: Mar 24 Transplant: Apr 28 🍅 Harvest: May 5 – Jun 2

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 Clay County

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

Soil pH

Your soil pH (5.3โ€“6.8) overlaps with Microgreens's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). 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

38
successive plantings in your 194-day season

Sow every 0.7 weeks. Last sowing by Oct 03 to harvest before frost.

For a dedicated fall crop, sow by Aug 15.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 463 gal / 100 sq ft

Monthly Watering Guide for Microgreens

Microgreens needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Microgreens Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr 4.3" 3" 1.3" ๐Ÿ’ง Light watering
May 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Jun 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Jul 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Aug 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Sep 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Oct 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Nov โ€” 2.2" 0" โ„๏ธ Dormant
Dec โ€” 1.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Clay County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Microgreens Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Microgreens needs ~224 GDD — county provides 3,104 GDD Excellent fit

Microgreens Planting Timeline โ€” Clay County, MO

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 โ€“ Mar 23
Transplant Outdoors April 13 Apr 13 โ€“ Apr 27
Direct Sow March 30 Mar 30 โ€“ Apr 20
Harvest April 20 Apr 20 โ€“ May 18
Fall Sowing August 15 Aug 15 โ€“ Aug 29

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
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 6a

๐Ÿ“† Growing Season

194 days in Clay County

Growing Tips for Microgreens in Clay County

Direct sow Microgreens outdoors after April 13 in Clay County when soil has warmed and frost danger has passed.

Your generous 194.0-day season in Clay 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 Clay County, MO?

Clay County is in Zone 6a with an average last frost of April 13. Plan your Microgreens planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clay County, MO?

Clay County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 13 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clay County gardeners in Zone 6a 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 Clay County, MO. Local conditions may vary. Last updated: April 2026.