When to Plant Endive in Caribou County, ID
Your May gardening checklist
May is a pivotal month for Caribou County, Idaho gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Set out endive seedlings
Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.
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Plant endive from seed, right in the garden
Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.
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.
Caribou County, Idaho is in USDA Zone 5a. The average last spring frost is May 30 and the first fall frost is September 16, giving you a growing season of approximately 109 days.
At an elevation of 6,562 feet, Caribou County receives approximately 15.3 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Endive to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Endive successfully. Mulch heavily to conserve soil moisture.
Caribou County Soil Profile
Soil Type
Loam
Soil pH
6.8-8.1
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 Caribou County
How your county's soil matches Endive's growing requirements.
Soil pH
Your soil pH (6.8–8.1) is more alkaline than Endive prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Caribou County is excellent for Endive — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Endive.
How to Plant Endive
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Endive
Sow every 5.1 weeks. Last sowing by Jul 13 to harvest before frost.
For a dedicated fall crop, sow by Jul 08.
Plant Water Budget
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 | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.4" | 0" | ❄️ Dormant |
| Apr | — | 1.7" | 0" | ❄️ Dormant |
| May | 3" | 1.6" | 1.4" | 💧 Light watering |
| Jun | 3" | 1" | 2" | 🚿 Regular watering |
| Jul | 3" | 1.5" | 1.5" | 🚿 Regular watering |
| Aug | 3" | 1.4" | 1.6" | 🚿 Regular watering |
| Sep | 3" | 1.2" | 1.8" | 🚿 Regular watering |
| Oct | — | 1.4" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Caribou 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 — Caribou County, ID
Endive Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 25 | Apr 25 – May 9 |
| Transplant Outdoors | May 30 | May 30 – Jun 13 |
| Direct Sow | May 16 | May 16 – Jun 6 |
| Harvest | July 18 | Jul 18 – Aug 22 |
| Fall Sowing | July 8 | Jul 8 – Jul 22 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing Harvest |
| August | 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 5a
📆 Growing Season
109 days in Caribou County
Growing Tips for Endive in Caribou County
Direct sow Endive outdoors after May 30 in Caribou 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 Caribou County, ID?
Caribou County is in Zone 5a with an average last frost of May 30. Plan your Endive planting based on this frost date — see the calendar above for exact timing.
What planting zone is Caribou County, ID?
Caribou County, Idaho is in USDA Hardiness Zone 5a. The average last spring frost is May 30 and first fall frost is September 16.
Your Caribou County Garden Planner — Free
A 24-page printable planner built for Caribou County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.