When to Plant Cilantro in USDA Zone 3b
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.
In Zone 3b, the average last spring frost is around May 10 and the first fall frost is around September 22, giving you a growing season of approximately 135 days.
Cilantro Planting Timeline — Zone 3b
Where Is USDA Zone 3b?
The map below highlights the states that contain Zone 3b. Click any state to see the Cilantro planting schedule for that location.
Cilantro Planting Calendar — Zone 3b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 29 | Mar 29 – Apr 12 |
| Transplant Outdoors | May 3 | May 3 – May 17 |
| Direct Sow | May 3 | May 3 – May 24 |
| Harvest | June 14 | Jun 14 – Aug 16 |
| Fall Sowing | June 30 | Jun 30 – Jul 14 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Fall Sowing Harvest |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Free Zone 3b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 3b with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Partial Shade (3-6 hours)
💧 Water
0.5"/week · Moderate — regular watering
Days to Maturity
40–60 days
Soil pH
6 – 7
Zone Temperature Range
-35°F to -30°F average annual minimum
Growing Season
135 days (Zone 3b average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 8 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Cilantro in Zone 3b
Sow every 4.6 weeks for continuous harvest throughout the season.
Growing Tips for Cilantro in Zone 3b
Zone 3b has a short growing season (~135 days). Start Cilantro indoors early and use season-extension techniques like row covers and cold frames.
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
Saving Cilantro Seeds
Recommended for Your Garden
Full-spectrum LED lights for starting seeds indoors when daylight is limited.
Warm soil for faster germination of heat-loving crops like tomatoes and peppers.
Protect plants from frost, wind, and pests while letting light and water through.
Related Plants
Cilantro in Other Zones
Cilantro by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Frequently Asked Questions
When should I plant Cilantro in Zone 3b?
In Zone 3b, plan your Cilantro planting around the average last frost date of May 10. Start seeds indoors around March 29. Direct sow outdoors around May 3. Transplant seedlings around May 3.
Can Cilantro grow in Zone 3b?
Yes, Cilantro can grow well in Zone 3b, hardy in USDA zones 2a through 11b. Zone 3b has a growing season of approximately 135 days, which is sufficient for Cilantro (40-60 days to maturity).
When can I harvest Cilantro in Zone 3b?
In Zone 3b, expect to harvest Cilantro from June 14 – August 16. Cilantro takes 40-60 days from planting to harvest.
What is the last frost date for Zone 3b?
The average last spring frost in Zone 3b is around May 10, and the first fall frost is around September 22. This gives a growing season of approximately 135 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Cilantro?
Good companion plants for Cilantro include Tomatoes, Peppers, Spinach. These companions can help with pest control, pollination, and nutrient sharing.
Plan Your Garden with Confidence
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