When to Plant Endive in Custer County, ID
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.
Custer County, Idaho is in USDA Zone 4a. The average last spring frost is June 18 and the first fall frost is September 5, giving you a growing season of approximately 79 days.
At an elevation of 5,189 feet, Custer County receives approximately 20.6 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Endive to ensure they mature before fall.
Custer County Soil Profile
Soil Type
Loam
Soil pH
6.3-8
Drainage
Well Drained
Plant Planting Risk Windows
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 Custer County
How your county's soil matches Endive's growing requirements.
Soil pH
Your soil pH (6.3–8.0) is more alkaline than Endive prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Custer County is excellent for Endive — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Endive.
How to Plant Endive
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Plant Water Budget
Water stress score is 6/10 — 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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 2.4" | 0" | ❄️ Dormant |
| May | — | 2.3" | 0" | ❄️ Dormant |
| Jun | 3" | 1.5" | 1.5" | 🚿 Regular watering |
| Jul | 3" | 2" | 1" | 💧 Light watering |
| Aug | 3" | 2.1" | 0.9" | 💧 Light watering |
| Sep | 3" | 1.7" | 1.3" | 💧 Light watering |
| Oct | — | 1.6" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Custer 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 Planting Timeline — Custer County, ID
Endive Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 7 | May 7 – May 21 |
| Transplant Outdoors | June 18 | Jun 18 – Jul 2 |
| Direct Sow | June 11 | Jun 11 – Jul 2 |
| Harvest | August 6 | Aug 6 – Sep 10 |
| Fall Sowing | June 13 | Jun 13 – Jun 27 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Transplant Outdoors Direct Sow |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
45–65 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 4a
📆 Growing Season
79 days in Custer County
Growing Tips for Endive in Custer County
Direct sow Endive outdoors after June 18 in Custer 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
Check more plant combinations with our Companion Planting Checker →
Endive in Other Locations
Frequently Asked Questions
When should I plant Endive in Custer County, ID?
Custer County is in Zone 4a with an average last frost of June 18. Plan your Endive planting based on this frost date — see the calendar above for exact timing.
What planting zone is Custer County, ID?
Custer County, Idaho is in USDA Hardiness Zone 4a. The average last spring frost is June 18 and first fall frost is September 5.
Plan Your Garden with Confidence
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