When to Plant Kabocha in Blaine County, ID
Kabocha is a Japanese winter squash with an exceptionally sweet, dense, chestnut-like flesh and dark green skin. It is a favorite in Asian cuisine for its rich, dry texture.
Blaine County, Idaho is in USDA Zone 5a. The average last spring frost is May 18 and the first fall frost is October 3, giving you a growing season of approximately 138 days.
At an elevation of 7,128 feet, Blaine County receives approximately 17.7 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Kabocha to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Kabocha successfully. Mulch heavily to conserve soil moisture.
Blaine County Soil Profile
Soil Type
Loam
Soil pH
6.7-8.4
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 Blaine County
How your county's soil matches Kabocha's growing requirements.
Soil pH
Your soil pH (6.7–8.4) is more alkaline than Kabocha prefers (6.0–7.5). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Blaine County is excellent for Kabocha — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Kabocha.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Kabocha.
How to Plant Kabocha
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Kabocha
Kabocha needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Kabocha Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 1.7" | 0" | ❄️ Dormant |
| May | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Jun | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Jul | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Aug | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Sep | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Oct | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Nov | — | 1.3" | 0" | ❄️ Dormant |
| Dec | — | 1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Blaine County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kabocha 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.
Kabocha Planting Timeline — Blaine County, ID
Kabocha Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 13 | Apr 13 – Apr 27 |
| Transplant Outdoors | June 1 | Jun 1 – Jun 15 |
| Direct Sow | May 25 | May 25 – Jun 15 |
| Harvest | August 31 | Aug 31 – Sep 28 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
85–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5a
📆 Growing Season
138 days in Blaine County
Growing Tips for Kabocha in Blaine County
Direct sow Kabocha outdoors after May 18 in Blaine County when soil has warmed and frost danger has passed.
Common pests for Kabocha in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
Blaine County receives only 18" of rain annually. Kabocha needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow after frost or start indoors. Harvest when the skin is hard and dull. The stem should be dry and corky. Stores well for 3-4 months in a cool, dry place.
Companion Planting
Good Companions
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Check more plant combinations with our Companion Planting Checker →
Kabocha in Other Locations
Frequently Asked Questions
When should I plant Kabocha in Blaine County, ID?
Blaine County is in Zone 5a with an average last frost of May 18. Plan your Kabocha planting based on this frost date — see the calendar above for exact timing.
What planting zone is Blaine County, ID?
Blaine County, Idaho is in USDA Hardiness Zone 5a. The average last spring frost is May 18 and first fall frost is October 3.
Plan Your Garden with Confidence
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