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When to Plant Borage in Cole County, MO

Borage is a self-seeding annual herb with star-shaped blue flowers that attract pollinators. Its leaves have a cucumber-like flavor and the flowers are edible.

Cole County, Missouri is in USDA Zone 6a. The average last spring frost is April 7 and the first fall frost is October 28, giving you a growing season of approximately 204 days.

At an elevation of 614 feet, Cole County receives approximately 39.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Borage during the growing season.

Cole County, MO (Zone 6a) Long season
204 days
Last Spring Frost April 7
204 growing days
First Fall Frost October 28

Cole County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (108 days to spare)
Start indoors: Feb 24 Transplant: Mar 24 🍅 Harvest: May 19 – Jul 7
Recommended (50%) ✓ Fits season (106 days to spare)
Start indoors: Mar 3 Transplant: Mar 31 🍅 Harvest: May 26 – Jul 14
Safe Start (90%) ✓ Fits season (107 days to spare)
Start indoors: Mar 18 Transplant: Apr 15 🍅 Harvest: Jun 10 – Jul 29

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
0.5″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Borage needs ~880 GDD — county provides 3,264 GDD Excellent fit

Borage Planting Timeline โ€” Cole County, MO

Borage Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 โ€“ Mar 17
Transplant Outdoors March 31 Mar 31 โ€“ Apr 14
Direct Sow March 24 Mar 24 โ€“ Apr 14
Fall Sowing August 19 Aug 19 โ€“ Sep 2
Harvest May 26 May 26 โ€“ Jul 14

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Transplant Outdoors 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

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

50โ€“60 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6a

Growing Season

204 days

Growing Tips for Cole County

Direct sow in spring as borage does not transplant well. Allow some plants to go to seed for next year. Young leaves are best; older leaves become bristly.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Borage in Cole County, MO?

Cole County is in Zone 6a with an average last frost of April 7. Plan your Borage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cole County, MO?

Cole County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 7 and first fall frost is October 28.

๐ŸŒฑ

Plan Your Garden with Confidence

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