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When to Plant Microgreens in New Haven County, CT

Microgreens are young seedlings of vegetables and herbs harvested at the cotyledon or first true leaf stage. They pack concentrated flavors and nutrients in a tiny package.

New Haven County, Connecticut is in USDA Zone 6b. The average last spring frost is April 23 and the first fall frost is October 19, giving you a growing season of approximately 179 days.

At an elevation of 509 feet, New Haven County receives approximately 49.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Microgreens during the growing season.

New Haven County, CT (Zone 6b) Moderate season
179 days
Last Spring Frost April 23
179 growing days
First Fall Frost October 19

New Haven County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (149 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: Apr 21 – May 19
Recommended (50%) ✓ Fits season (144 days to spare)
Start indoors: Mar 19 Transplant: Apr 23 🍅 Harvest: Apr 30 – May 28
Safe Start (90%) ✓ Fits season (135 days to spare)
Start indoors: Apr 11 Transplant: May 16 🍅 Harvest: May 23 – Jun 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
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Microgreens needs ~234 GDD — county provides 2,998 GDD Excellent fit

Microgreens Planting Timeline โ€” New Haven County, CT

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 โ€“ Apr 2
Transplant Outdoors April 23 Apr 23 โ€“ May 7
Direct Sow April 9 Apr 9 โ€“ Apr 30
Fall Sowing August 10 Aug 10 โ€“ Aug 24
Harvest April 30 Apr 30 โ€“ May 28

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors Transplant Outdoors Direct Sow Harvest
May Transplant Outdoors Harvest
June โ€”
July โ€”
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

7โ€“21 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

179 days

Growing Tips for New Haven County

Sow seeds densely on shallow trays of moist growing medium. Cover until germination, then provide light. Harvest with scissors when 1-3 inches tall. Grow year-round indoors.

Frequently Asked Questions

When should I plant Microgreens in New Haven County, CT?

New Haven County is in Zone 6b with an average last frost of April 23. Plan your Microgreens planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is New Haven County, CT?

New Haven County, Connecticut is in USDA Hardiness Zone 6b. The average last spring frost is April 23 and first fall frost is October 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help New Haven 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 New Haven County, CT. Local conditions may vary. Last updated: April 2026.