When to plant Pumpkin in Harrison County, IA
In Harrison County, plant Pumpkin in spring between May 1 and May 22, once soil temps hold above 50°F. Harrison County's last frost averages April 24, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between and — roughly 85–120 days before the first frost on October 10.
When to Plant Pumpkin in Harrison County, IA
Pumpkins are large-fruited squash varieties grown for eating, decoration, and seed production. They require ample space and a long, warm growing season.
Harrison County, Iowa is in USDA Zone 5b. The average last spring frost is April 24 and the first fall frost is October 10, giving you a growing season of approximately 169 days.
At an elevation of 1,345 feet, Harrison County receives approximately 35.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Pumpkin to ensure they mature before fall.
Harrison County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Pumpkin Planting Timeline — Harrison County, IA
Pumpkin Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 20 | Mar 20 – Apr 3 |
| Transplant Outdoors | May 8 | May 8 – May 22 |
| Direct Sow | May 1 | May 1 – May 22 |
| Harvest | August 7 | Aug 7 – Sep 25 |
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
85–120 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
169 days in Harrison County
Growing Tips for Harrison County
Direct sow on mounds after last frost. Allow 6-10 feet between plants. Slip a board under developing fruit to prevent rot. Harvest when rind is hard and deep in color.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Pumpkin in Other Locations
Frequently Asked Questions
When should I plant Pumpkin in Harrison County, IA?
Harrison County is in Zone 5b with an average last frost of April 24. Plan your Pumpkin planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harrison County, IA?
Harrison County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 24 and first fall frost is October 10.
When should I plant Pumpkin in Harrison County, IA?
In Harrison County, IA, plant Pumpkin after the last frost (around April 24) and before the first frost (around October 10). Best results when soil holds above 50°F.
What growing zone is Harrison County, IA for Pumpkin?
Harrison County sits in USDA Zone 5b. Pumpkin grows reliably in zones 3a through 10b, so it's a good fit here.
Can Pumpkin grow in Harrison County's climate?
Yes — Pumpkin grows well in Harrison County's temperate climate. Harrison County averages a 169-day frost-free season, with last frost around April 24 and first frost around October 10.
Your Harrison County Garden Planner — Free
A 22-page printable planner built for Harrison County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.