Blog

When to Plant Mint in New London County, CT

New London County, Connecticut Zone 7a May

This month in New London County, Connecticut

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 23
Avg. first frost October 18
Soil temp (4") 63°F
Watering Low
Pest pressure Low
Daylight 14.3 hrs

Instant PDF download. No spam, unsubscribe any time.

Mint is a vigorous perennial herb with refreshing, aromatic leaves used in teas, cocktails, and cooking. It spreads aggressively by underground runners.

New London County, Connecticut is in USDA Zone 7a. The average last spring frost is April 23 and the first fall frost is October 18, giving you a growing season of approximately 178 days.

At an elevation of 766 feet, New London County receives approximately 49.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Mint during the growing season.

New London County, CT (Zone 7a) Moderate season
178 days
Last Spring Frost April 23
178 growing days
First Fall Frost October 18

New London County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (41 days to spare)
Transplant: Apr 21 🍅 Harvest: Jun 23 – Sep 1
Recommended (50%) ✓ Fits season (38 days to spare)
Transplant: Apr 30 🍅 Harvest: Jul 2 – Sep 10
Safe Start (90%) ✓ Fits season (31 days to spare)
Transplant: May 22 🍅 Harvest: Jul 24 – Oct 2

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.

Soil Compatibility in New London County

How your county's soil matches Mint's growing requirements.

Soil pH

Your soil pH (5.0–6.6) is more acidic than Mint prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in New London County is excellent for Mint — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Mint.

Organic Matter

Organic matter is moderate (3.6%). Annual compost additions will help Mint.

How to Plant Mint

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Mint

3
successive plantings in your 178-day season

Sow every 6.9 weeks. Last sowing by Jul 20 to harvest before frost.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Mint

Mint needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Mint Needs Rainfall You Supplement Action
Jan 3.5" 0" ❄️ Dormant
Feb 3.5" 0" ❄️ Dormant
Mar 4" 0" ❄️ Dormant
Apr 3" 4.7" 0" ✅ Rainfall sufficient
May 3" 4.4" 0" ✅ Rainfall sufficient
Jun 3" 4.3" 0" ✅ Rainfall sufficient
Jul 3" 5.1" 0" ✅ Rainfall sufficient
Aug 3" 3.9" 0" ✅ Rainfall sufficient
Sep 3" 4.1" 0" ✅ Rainfall sufficient
Oct 3" 4.5" 0" ✅ Rainfall sufficient
Nov 3.9" 0" ❄️ Dormant
Dec 3.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in New London County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Mint Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Mint needs ~1,144 GDD — county provides 2,714 GDD Excellent fit

Mint Planting Timeline — New London County, CT

Mint Planting Calendar

Activity When Date Range
Transplant Outdoors April 30 Apr 30 – May 14
Harvest July 2 Jul 2 – Sep 10

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May Transplant Outdoors
June
July Harvest
August Harvest
September Harvest
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

178 days in New London County

Growing Tips for Mint in New London County

Direct sow Mint outdoors after April 23 in New London County when soil has warmed and frost danger has passed.

General growing tips

Always grow mint in containers or with underground barriers to control spreading. Harvest regularly to keep plants compact. Cut plants back in late summer for a fresh fall flush.

Companion Planting

Good Companions

Avoid Planting Near

  • Parsley

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mint in New London County, CT?

New London County is in Zone 7a with an average last frost of April 23. Plan your Mint planting based on this frost date — see the calendar above for exact timing.

What planting zone is New London County, CT?

New London County, Connecticut is in USDA Hardiness Zone 7a. The average last spring frost is April 23 and first fall frost is October 18.

🌱

Your New London County Garden Planner — Free

A 24-page printable planner built for New London County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.