When to plant Leeks in Harrison County, IA
Spring Leeks in Harrison County goes in April 10–May 1, once nighttime temps stop dipping near freezing. A second sowing from August 1 to August 15 extends the harvest into fall.
When to Plant Leeks in Harrison County, IA
Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.
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 Leeks to ensure they mature before fall.
Harrison County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Leeks Planting Timeline — Harrison County, IA
Leeks Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 20 | Mar 20 – Apr 3 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 10 | Apr 10 – May 1 |
| Harvest | July 24 | Jul 24 – Oct 9 |
| Fall Sowing | August 1 | Aug 1 – Aug 15 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
90–150 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
169 days in Harrison County
Growing Tips for Harrison County
Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Leeks in Other Locations
Frequently Asked Questions
When should I plant Leeks in Harrison County, IA?
Harrison County is in Zone 5b with an average last frost of April 24. Plan your Leeks 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 Leeks in Harrison County, IA?
In Harrison County, IA, plant Leeks 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 Leeks?
Harrison County sits in USDA Zone 5b. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.
Can Leeks grow in Harrison County's climate?
Yes — Leeks 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.