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When to Plant Endive in Johnson 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.

Johnson County, Iowa is in USDA Zone 5a. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.

At an elevation of 1,204 feet, Johnson County receives approximately 40.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Endive during the growing season.

Johnson County, IA (Zone 5a) Moderate season
170 days
Last Spring Frost April 24
170 growing days
First Fall Frost October 11

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (90 days to spare)
Start indoors: Mar 12 Transplant: Apr 16 🍅 Harvest: Jun 4 – Jul 9
Recommended (50%) ✓ Fits season (86 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: Jun 12 – Jul 17
Safe Start (90%) ✓ Fits season (83 days to spare)
Start indoors: Apr 3 Transplant: May 8 🍅 Harvest: Jun 26 – Jul 31

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 Johnson County

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

Soil pH

Your soil pH (6.2โ€“7.3) overlaps with Endive's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Endive.

How to Plant Endive

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 Endive

4
successive plantings in your 170-day season

Sow every 5.1 weeks. Last sowing by Aug 07 to harvest before frost.

For a dedicated fall crop, sow by Aug 02.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Endive needs ~756 GDD — county provides 2,337 GDD Excellent fit

Endive Planting Timeline โ€” Johnson County, IA

Endive Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 โ€“ Apr 3
Transplant Outdoors April 24 Apr 24 โ€“ May 8
Direct Sow April 10 Apr 10 โ€“ May 1
Fall Sowing August 2 Aug 2 โ€“ Aug 16
Harvest June 12 Jun 12 โ€“ Jul 17

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 Harvest
August Fall Sowing
September โ€”
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

45โ€“65 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

170 days in Johnson County

Growing Tips for Endive in Johnson County

Direct sow Endive outdoors after April 24 in Johnson County when soil has warmed and frost danger has passed.

Your generous 170.0-day season in Johnson County allows multiple plantings of Endive. Sow every 22.0 days for continuous harvest.

Common pests for Endive in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Johnson County, IA?

Johnson County is in Zone 5a with an average last frost of April 24. Plan your Endive planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Johnson County, IA?

Johnson County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 24 and first fall frost is October 11.

๐ŸŒฑ

Plan Your Garden with Confidence

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