When to Plant Cilantro in Calhoun County, IA
Cilantro is a dual-purpose herb providing fresh leaves (cilantro) and dried seeds (coriander). It bolts quickly in heat, producing flowers beloved by beneficial insects.
Calhoun County, Iowa is in USDA Zone 4b. The average last spring frost is April 25 and the first fall frost is October 6, giving you a growing season of approximately 164 days.
At an elevation of 1,052 feet, Calhoun County receives approximately 30.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Cilantro to ensure they mature before fall.
Calhoun County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.8
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
Cilantro Planting Timeline — Calhoun County, IA
Cilantro Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 14 | Mar 14 – Mar 28 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | April 18 | Apr 18 – May 9 |
| Fall Sowing | July 14 | Jul 14 – Jul 28 |
| Harvest | May 30 | May 30 – Aug 1 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow Harvest |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Partial Shade (3-6 hours)
Water
Moderate — regular watering
Days to Maturity
40–60 days
Soil pH
6 – 7
USDA Zone
Zone 4b
Growing Season
164 days
Growing Tips for Calhoun County
Succession sow every 2-3 weeks. Provide afternoon shade in warm weather. Harvest leaves before flowering or allow some plants to go to seed for coriander and self-sowing.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Cilantro in Other Locations
Frequently Asked Questions
When should I plant Cilantro in Calhoun County, IA?
Calhoun County is in Zone 4b with an average last frost of April 25. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.
What planting zone is Calhoun County, IA?
Calhoun County, Iowa is in USDA Hardiness Zone 4b. The average last spring frost is April 25 and first fall frost is October 6.
Plan Your Garden with Confidence
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