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When to Plant Spinach in Franklin County, MO

Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.

Franklin County, Missouri is in USDA Zone 6a. The average last spring frost is April 10 and the first fall frost is October 27, giving you a growing season of approximately 200 days.

At an elevation of 1,180 feet, Franklin County receives approximately 38.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90ยฐF, providing good warmth for Spinach during the growing season.

Franklin County, MO (Zone 6a) Long season
200 days
Last Spring Frost April 10
200 growing days
First Fall Frost October 27

Franklin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (100 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 9 – Jul 11
Recommended (50%) ✓ Fits season (102 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: May 15 – Jul 17
Safe Start (90%) ✓ Fits season (102 days to spare)
Start indoors: Mar 19 Transplant: Apr 23 🍅 Harvest: May 28 – Jul 30

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 Franklin County

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

Soil pH

Your soil pH (5.7โ€“6.8) is more acidic than Spinach prefers (6.5โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

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

How to Plant Spinach

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Spinach

6
successive plantings in your 200-day season

Sow every 4 weeks. Last sowing by Sep 07 to harvest before frost.

For a dedicated fall crop, sow by Aug 18.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Spinach

Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Spinach Needs Rainfall You Supplement Action
Jan โ€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 1.9" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr 3" 4" 0" โœ… Rainfall sufficient
May 3" 3.9" 0" โœ… Rainfall sufficient
Jun 3" 4.8" 0" โœ… Rainfall sufficient
Jul 3" 4.7" 0" โœ… Rainfall sufficient
Aug 3" 3.5" 0" โœ… Rainfall sufficient
Sep 3" 3.2" 0" โœ… Rainfall sufficient
Oct 3" 3.2" 0" โœ… Rainfall sufficient
Nov โ€” 2.5" 0" โ„๏ธ Dormant
Dec โ€” 2.3" 0" โ„๏ธ Dormant

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

Spinach 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.

Spinach needs ~744 GDD — county provides 3,500 GDD Excellent fit

Spinach Planting Timeline โ€” Franklin County, MO

Spinach Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors April 10 Apr 10 โ€“ Apr 24
Direct Sow March 27 Mar 27 โ€“ Apr 17
Harvest May 15 May 15 โ€“ Jul 17
Fall Sowing August 18 Aug 18 โ€“ Sep 1

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.7"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

35โ€“50 days

๐Ÿงช Soil pH

Needs 6.5โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

200 days in Franklin County

Growing Tips for Spinach in Franklin County

Direct sow Spinach outdoors after April 10 in Franklin County when soil has warmed and frost danger has passed.

Your generous 200.0-day season in Franklin County allows multiple plantings of Spinach. Sow every 17.0 days for continuous harvest.

General growing tips

Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.

Recommended Spinach Varieties for Franklin County

Slow-bolting spinach for warm springs โ€” best as fall crop here

Bloomsdale Long Standing Tyee Space

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Spinach Seeds
Life Cycle Annual
Pollination Wind Pollinated
How to Collect Let plants bolt. Harvest seed stalks when seeds turn tan.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Wind pollinated โ€” isolate 1/2 mile for purity. Easy to let bolt in heat.

Frequently Asked Questions

When should I plant Spinach in Franklin County, MO?

Franklin County is in Zone 6a with an average last frost of April 10. Plan your Spinach planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Franklin County, MO?

Franklin County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 10 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Franklin 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 Franklin County, MO. Local conditions may vary. Last updated: April 2026.