When to Plant Kabocha in Guthrie County, IA
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.
Guthrie County, Iowa is in USDA Zone 5a. The average last spring frost is April 26 and the first fall frost is October 6, giving you a growing season of approximately 163 days.
At an elevation of 1,378 feet, Guthrie County receives approximately 31.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Kabocha to ensure they mature before fall.
Guthrie County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.7
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.
Plant Water Budget
Kabocha Planting Timeline — Guthrie County, IA
Kabocha Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 22 | Mar 22 – Apr 5 |
| Transplant Outdoors | May 10 | May 10 – May 24 |
| Direct Sow | May 3 | May 3 – May 24 |
| Harvest | August 9 | Aug 9 – Sep 6 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
85–100 days
Soil pH
6 – 7.5
USDA Zone
Zone 5a
Growing Season
163 days
Growing Tips for Guthrie County
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
Avoid Planting Near
Level Up Your Garden
Kabocha in Other Locations
Frequently Asked Questions
When should I plant Kabocha in Guthrie County, IA?
Guthrie County is in Zone 5a with an average last frost of April 26. Plan your Kabocha planting based on this frost date — see the calendar above for exact timing.
What planting zone is Guthrie County, IA?
Guthrie County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 26 and first fall frost is October 6.
Plan Your Garden with Confidence
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