When to Plant Cilantro in Sioux 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.
Sioux County, Iowa is in USDA Zone 4b. The average last spring frost is May 1 and the first fall frost is October 3, giving you a growing season of approximately 155 days.
At an elevation of 1,212 feet, Sioux County receives approximately 39.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Cilantro to ensure they mature before fall.
Sioux County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-7
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
Cilantro Planting Timeline — Sioux County, IA
Cilantro 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 24 | Apr 24 – May 15 |
| Fall Sowing | July 11 | Jul 11 – Jul 25 |
| Harvest | June 5 | Jun 5 – Aug 7 |
Plant 0.5" deep · 8" 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 | 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
155 days
Growing Tips for Sioux 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 Sioux County, IA?
Sioux County is in Zone 4b with an average last frost of May 1. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sioux County, IA?
Sioux County, Iowa is in USDA Hardiness Zone 4b. The average last spring frost is May 1 and first fall frost is October 3.
Plan Your Garden with Confidence
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