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When to Plant Belgian Endive in Clark County, ID

Clark County, Idaho Zone 4a April

Your April gardening checklist

Welcome to April in Zone 4a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost June 7
Avg. first frost September 10
Soil temp (4") 20°F
Watering High
Pest pressure Low
Daylight 13.2 hrs
Get ahead of May
  • Direct-sowing: belgian endive

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Belgian endive is produced by forcing chicory roots in darkness to create tight, pale, torpedo-shaped heads called chicons. They have a mild bitterness and elegant crunch.

Clark County, Idaho is in USDA Zone 4a. The average last spring frost is June 7 and the first fall frost is September 10, giving you a growing season of approximately 95 days.

At an elevation of 7,493 feet, Clark County receives approximately 21.9 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Belgian Endive to ensure they mature before fall.

Clark County, ID (Zone 4a) Very short season
95 days
Last Spring Frost June 7
95 growing days
First Fall Frost September 10

Clark County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 11 Transplant: May 23 🍅 Harvest: Sep 12 – Oct 17
Recommended (50%) ✗ May not fit
Start indoors: Apr 26 Transplant: Jun 7 🍅 Harvest: Sep 27 – Nov 1
Safe Start (90%) ✗ May not fit
Start indoors: May 10 Transplant: Jun 21 🍅 Harvest: Oct 11 – Nov 15

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 Clark County

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

Soil pH

Your soil pH (6.8–7.8) is more alkaline than Belgian Endive prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Belgian Endive.

How to Plant Belgian Endive

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 32 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Belgian Endive

Belgian Endive needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Belgian Endive Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 2.5" 0" ❄️ Dormant
May 2.5" 0" ❄️ Dormant
Jun 4.3" 1.5" 2.8" 🚿 Regular watering
Jul 4.3" 1.7" 2.6" 🚿 Regular watering
Aug 4.3" 2.2" 2.1" 💧 Light watering
Sep 4.3" 1.7" 2.6" 🚿 Regular watering
Oct 1.8" 0" ❄️ Dormant
Nov 1.6" 0" ❄️ Dormant
Dec 1.3" 0" ❄️ Dormant

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

Belgian 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.

Belgian Endive needs ~1,495 GDD — county provides 1,092 GDD May not mature

Belgian Endive Planting Timeline — Clark County, ID

Belgian Endive Planting Calendar

Activity When Date Range
Start Indoors April 26 Apr 26 – May 10
Transplant Outdoors June 7 Jun 7 – Jun 21
Direct Sow May 31 May 31 – Jun 21
Harvest September 27 Sep 27 – Nov 1
Fall Sowing June 18 Jun 18 – Jul 2

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

110–150 days

🧪 Soil pH

Needs 5.5–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 4a

📆 Growing Season

95 days in Clark County

Growing Tips for Belgian Endive in Clark County

Direct sow Belgian Endive outdoors after June 07 in Clark County when soil has warmed and frost danger has passed.

Your 95.0-day growing season in Clark County is tight for Belgian Endive (110.0-150.0 days to maturity). Start indoors and choose early-maturing varieties.

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

Clark County receives only 22" of rain annually. Belgian Endive needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Grow chicory roots in the garden during summer, then dig in fall. Trim tops and force roots in moist sand in a dark cellar at 50-60F. Chicons emerge in 3-4 weeks.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Belgian Endive in Clark County, ID?

Clark County is in Zone 4a with an average last frost of June 7. Plan your Belgian Endive planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clark County, ID?

Clark County, Idaho is in USDA Hardiness Zone 4a. The average last spring frost is June 7 and first fall frost is September 10.

🌱

Your Clark County Garden Planner — Free

A 24-page printable planner built for Clark County (Zone 4a). 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 Clark County, ID. Local conditions may vary. Last updated: April 2026.

Sources & credits

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