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When to Plant Cilantro in Middlesex County, MA

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.

Middlesex County, Massachusetts is in USDA Zone 6b. The average last spring frost is April 24 and the first fall frost is October 17, giving you a growing season of approximately 176 days.

At an elevation of 117 feet, Middlesex County receives approximately 43.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90ยฐF, providing good warmth for Cilantro during the growing season.

Middlesex County, MA (Zone 6b) Moderate season
176 days
Last Spring Frost April 24
176 growing days
First Fall Frost October 17

Middlesex County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (76 days to spare)
Start indoors: Mar 16 Transplant: Apr 13 🍅 Harvest: May 25 – Jul 27
Recommended (50%) ✓ Fits season (78 days to spare)
Start indoors: Mar 20 Transplant: Apr 17 🍅 Harvest: May 29 – Jul 31
Safe Start (90%) ✓ Fits season (74 days to spare)
Start indoors: Apr 8 Transplant: May 6 🍅 Harvest: Jun 17 – Aug 19

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
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Cilantro needs ~875 GDD — county provides 3,080 GDD Excellent fit

Cilantro Planting Timeline โ€” Middlesex County, MA

Cilantro Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 โ€“ Apr 3
Transplant Outdoors April 17 Apr 17 โ€“ May 1
Direct Sow April 10 Apr 10 โ€“ May 1
Fall Sowing August 8 Aug 8 โ€“ Aug 22
Harvest May 29 May 29 โ€“ Jul 31

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
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 6b

Growing Season

176 days

Growing Tips for Middlesex 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 Middlesex County, MA?

Middlesex County is in Zone 6b with an average last frost of April 24. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Middlesex County, MA?

Middlesex County, Massachusetts is in USDA Hardiness Zone 6b. The average last spring frost is April 24 and first fall frost is October 17.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Middlesex County gardeners in Zone 6b 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 Middlesex County, MA. Local conditions may vary. Last updated: April 2026.