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When to Plant Endive in Mahaska County, IA

Endive is a leafy green with a slightly bitter flavor, available in curly (frisee) and broad-leaved (escarole) types. It adds texture and complexity to salads.

Mahaska County, Iowa is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 9, giving you a growing season of approximately 165 days.

At an elevation of 511 feet, Mahaska County receives approximately 32.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Endive to ensure they mature before fall.

Mahaska County, IA (Zone 5a) Moderate season
165 days
Last Spring Frost April 27
165 growing days
First Fall Frost October 9

Mahaska County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (82 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Jun 9 – Jul 14
Recommended (50%) ✓ Fits season (81 days to spare)
Start indoors: Mar 23 Transplant: Apr 27 🍅 Harvest: Jun 15 – Jul 20
Safe Start (90%) ✓ Fits season (77 days to spare)
Start indoors: Apr 9 Transplant: May 14 🍅 Harvest: Jul 2 – Aug 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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 265 gal / 100 sq ft
Endive needs ~674 GDD — county provides 2,021 GDD Excellent fit

Endive Planting Timeline โ€” Mahaska County, IA

Endive Planting Calendar

Activity When Date Range
Start Indoors March 23 Mar 23 โ€“ Apr 6
Transplant Outdoors April 27 Apr 27 โ€“ May 11
Direct Sow April 13 Apr 13 โ€“ May 4
Fall Sowing July 31 Jul 31 โ€“ Aug 14
Harvest June 15 Jun 15 โ€“ Jul 20

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

Month-by-Month Timeline

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

45โ€“65 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 5a

Growing Season

165 days

Growing Tips for Mahaska County

Sow seeds directly in spring or fall. Blanch heads by tying outer leaves together 2-3 weeks before harvest to reduce bitterness. Keep soil evenly moist.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Level Up Your Garden

Frequently Asked Questions

When should I plant Endive in Mahaska County, IA?

Mahaska County is in Zone 5a with an average last frost of April 27. Plan your Endive planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Mahaska County, IA?

Mahaska County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 9.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Mahaska County gardeners in Zone 5a 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 Mahaska County, IA. Local conditions may vary. Last updated: April 2026.