When to plant Leeks in Delaware County, IA
For Delaware County, gardeners: plant Leeks April 18 through May 9 once soil reads 50°F. A second sowing from July 29 to August 12 extends the harvest into fall.
When to Plant Leeks in Delaware 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.
Delaware County, Iowa is in USDA Zone 5a. The average last spring frost is May 2 and the first fall frost is October 7, giving you a growing season of approximately 158 days.
At an elevation of 974 feet, Delaware County receives approximately 31.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Leeks to ensure they mature before fall.
Delaware County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Leeks Planting Timeline — Delaware County, IA
Leeks Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 28 | Mar 28 – Apr 11 |
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Direct Sow | April 18 | Apr 18 – May 9 |
| Harvest | August 1 | Aug 1 – Oct 17 |
| Fall Sowing | July 29 | Jul 29 – Aug 12 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing |
| 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 5a
📆 Growing Season
158 days in Delaware County
Growing Tips for Delaware 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
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Leeks in Other Locations
Frequently Asked Questions
When should I plant Leeks in Delaware County, IA?
Delaware County is in Zone 5a with an average last frost of May 2. Plan your Leeks planting based on this frost date — see the calendar above for exact timing.
What planting zone is Delaware County, IA?
Delaware County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is May 2 and first fall frost is October 7.
When should I plant Leeks in Delaware County, IA?
In Delaware County, IA, plant Leeks after the last frost (around May 2) and before the first frost (around October 7). Best results when soil holds above 50°F.
What growing zone is Delaware County, IA for Leeks?
Delaware County sits in USDA Zone 5a. Leeks grows reliably in zones 3a through 10b, so it's a good fit here.
Can Leeks grow in Delaware County's climate?
Yes — Leeks grows well in Delaware County's temperate climate. Delaware County averages a 158-day frost-free season, with last frost around May 2 and first frost around October 7.
Your Delaware County Garden Planner — Free
A 22-page printable planner built for Delaware 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.