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When to Plant Endive in Twin Falls County, ID

Twin Falls County, Idaho Zone 6b May

Your May planting checklist for Twin Falls County, Idaho

May is a pivotal month for Twin Falls County, Idaho gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 10
Avg. first frost October 4
Soil temp (4") 49°F
Watering High
Pest pressure Low
Daylight 14.4 hrs
  1. Move endive from tray to bed

    Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.

Coming up in June — start thinking about
  • Starting indoors: endive
  • First harvests: endive

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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.

Twin Falls County, Idaho is in USDA Zone 6b. The average last spring frost is May 10 and the first fall frost is October 4, giving you a growing season of approximately 147 days.

At an elevation of 4,584 feet, Twin Falls County receives approximately 21.8 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Endive during the growing season.

Twin Falls County, ID (Zone 6b) Short season
147 days
Last Spring Frost May 10
147 growing days
First Fall Frost October 4

Twin Falls County Soil Profile

Soil Type

Loam

Soil pH

6.5-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (66 days to spare)
Start indoors: Mar 27 Transplant: May 1 🍅 Harvest: Jun 19 – Jul 24
Recommended (50%) ✓ Fits season (63 days to spare)
Start indoors: Apr 5 Transplant: May 10 🍅 Harvest: Jun 28 – Aug 2
Safe Start (90%) ✓ Fits season (56 days to spare)
Start indoors: Apr 30 Transplant: Jun 4 🍅 Harvest: Jul 23 – Aug 27

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 Twin Falls County

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

Soil pH

Your soil pH (6.5–8.0) is more alkaline than Endive prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Twin Falls County is excellent for Endive — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). 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

3
successive plantings in your 147-day season

Sow every 5.1 weeks. Last sowing by Jul 31 to harvest before frost.

For a dedicated fall crop, sow by Jul 26.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.6″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 121 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Endive

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

Month Endive Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 2.6" 0" ❄️ Dormant
May 3" 2.3" 0.7" 💧 Light watering
Jun 3" 1.6" 1.4" 💧 Light watering
Jul 3" 1.9" 1.1" 💧 Light watering
Aug 3" 2.4" 0.6" 💧 Light watering
Sep 3" 1.9" 1.1" 💧 Light watering
Oct 3" 2.1" 0.9" 💧 Light watering
Nov 1.3" 0" ❄️ Dormant
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Twin Falls County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Endive 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" — every day above 50°F 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.

Endive needs ~798 GDD — county provides 2,131 GDD Excellent fit

Endive Planting Timeline — Twin Falls County, ID

Endive Planting Calendar

Activity When Date Range
Start Indoors April 5 Apr 5 – Apr 19
Transplant Outdoors May 10 May 10 – May 24
Direct Sow April 26 Apr 26 – May 17
Harvest June 28 Jun 28 – Aug 2
Fall Sowing July 26 Jul 26 – Aug 9

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Only during dry spells

📅 Days to Maturity

45–65 days

🧪 Soil pH

Needs 5.5–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6b

📆 Growing Season

147 days in Twin Falls County

Growing Tips for Endive in Twin Falls County

Direct sow Endive outdoors after May 10 in Twin Falls County when soil has warmed and frost danger has passed.

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Endive in Twin Falls County, ID?

Twin Falls County is in Zone 6b with an average last frost of May 10. Plan your Endive planting based on this frost date — see the calendar above for exact timing.

What planting zone is Twin Falls County, ID?

Twin Falls County, Idaho is in USDA Hardiness Zone 6b. The average last spring frost is May 10 and first fall frost is October 4.

🌱

Your Twin Falls County Garden Planner — Free

A 24-page printable planner built for Twin Falls County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Twin Falls County, ID. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.