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When to Plant Cilantro in Carbon County, PA

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.

Carbon County, Pennsylvania is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 19, giving you a growing season of approximately 176 days.

At an elevation of 1,110 feet, Carbon County receives approximately 44.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Cilantro to ensure they mature before fall.

Carbon County, PA (Zone 5b) Moderate season
176 days
Last Spring Frost April 26
176 growing days
First Fall Frost October 19

Carbon County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (79 days to spare)
Start indoors: Mar 15 Transplant: Apr 12 🍅 Harvest: May 24 – Jul 26
Recommended (50%) ✓ Fits season (78 days to spare)
Start indoors: Mar 22 Transplant: Apr 19 🍅 Harvest: May 31 – Aug 2
Safe Start (90%) ✓ Fits season (74 days to spare)
Start indoors: Apr 9 Transplant: May 7 🍅 Harvest: Jun 18 – Aug 20

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

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Cilantro needs ~650 GDD — county provides 2,288 GDD Excellent fit

Cilantro Planting Timeline โ€” Carbon County, PA

Cilantro Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 โ€“ Apr 5
Transplant Outdoors April 19 Apr 19 โ€“ May 3
Direct Sow April 12 Apr 12 โ€“ May 3
Fall Sowing August 10 Aug 10 โ€“ Aug 24
Harvest May 31 May 31 โ€“ Aug 2

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow Harvest
June Harvest
July Harvest
August Fall Sowing Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

40โ€“60 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

176 days

Growing Tips for Carbon 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

  • Fennel

Level Up Your Garden

Frequently Asked Questions

When should I plant Cilantro in Carbon County, PA?

Carbon County is in Zone 5b with an average last frost of April 26. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Carbon County, PA?

Carbon County, Pennsylvania is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Carbon County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Carbon County, PA. Local conditions may vary. Last updated: April 2026.