When to Plant Scallions in Franklin County, IA
Scallions (green onions) are mild-flavored alliums harvested for their slender green tops and white bases. They are quick-growing and perfect for succession planting.
Franklin County, Iowa is in USDA Zone 4b. The average last spring frost is April 30 and the first fall frost is October 7, giving you a growing season of approximately 160 days.
At an elevation of 1,145 feet, Franklin County receives approximately 41.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Scallions to ensure they mature before fall.
Franklin County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7
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
Scallions Planting Timeline — Franklin County, IA
Scallions Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | April 30 | Apr 30 – May 14 |
| Direct Sow | April 23 | Apr 23 – May 14 |
| Fall Sowing | July 15 | Jul 15 – Jul 29 |
| Harvest | June 25 | Jun 25 – Jul 23 |
Plant 0.5" deep · 6" apart · Rows 12" 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 | Harvest |
| July | Fall Sowing Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
50–70 days
Soil pH
6 – 7
USDA Zone
Zone 4b
Growing Season
160 days
Growing Tips for Franklin County
Direct sow every 3 weeks for continuous harvest. Thin to 1 inch apart or grow in clusters. Harvest when pencil-thick by pulling or cutting at soil level.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Scallions in Other Locations
Frequently Asked Questions
When should I plant Scallions in Franklin County, IA?
Franklin County is in Zone 4b with an average last frost of April 30. Plan your Scallions planting based on this frost date — see the calendar above for exact timing.
What planting zone is Franklin County, IA?
Franklin County, Iowa is in USDA Hardiness Zone 4b. The average last spring frost is April 30 and first fall frost is October 7.
Plan Your Garden with Confidence
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