Blog

When to Plant Mizuna in New London County, CT

New London County, Connecticut Zone 7a May

Your May gardening checklist

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
  1. Sow mizuna in trays indoors

    These need a head start before your last frost (April 23). Sow into cells now so you're ready to transplant in a few weeks.

  2. Harvest mizuna as they ripen

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Before June arrives, get these ready
  • First harvests: mizuna

Instant PDF download. No spam, unsubscribe any time.

Mizuna is a mild-flavored Japanese mustard green with feathery, deeply serrated leaves. It is fast-growing and makes an excellent addition to salads and stir-fries.

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 Mizuna 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 (118 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: May 19 – Jun 16
Recommended (50%) ✓ Fits season (115 days to spare)
Start indoors: Mar 19 Transplant: Apr 23 🍅 Harvest: May 28 – Jun 25
Safe Start (90%) ✓ Fits season (108 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: Jun 19 – Jul 17

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 Mizuna's growing requirements.

Soil pH

Your soil pH (5.0–6.6) is more acidic than Mizuna prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Mizuna.

Organic Matter

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

How to Plant Mizuna

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Mizuna

7
successive plantings in your 178-day season

Sow every 3.4 weeks. Last sowing by Sep 03 to harvest before frost.

For a dedicated fall crop, sow by Aug 09.

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

Monthly Watering Guide for Mizuna

Mizuna needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Mizuna Needs Rainfall You Supplement Action
Jan 3.5" 0" ❄️ Dormant
Feb 3.5" 0" ❄️ Dormant
Mar 4" 0" ❄️ Dormant
Apr 4.3" 4.7" 0" ✅ Rainfall sufficient
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 5.1" 0" ✅ Rainfall sufficient
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 4.1" 0.2" 💧 Light watering
Oct 4.3" 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.

Mizuna 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.

Mizuna needs ~572 GDD — county provides 2,714 GDD Excellent fit

Mizuna Planting Timeline — New London County, CT

Mizuna Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 – Apr 2
Transplant Outdoors April 23 Apr 23 – May 7
Direct Sow April 9 Apr 9 – Apr 30
Harvest May 28 May 28 – Jun 25
Fall Sowing August 9 Aug 9 – Aug 23

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

30–45 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

178 days in New London County

Growing Tips for Mizuna in New London County

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

Your generous 178.0-day season in New London County allows multiple plantings of Mizuna. Sow every 15.0 days for continuous harvest.

Common pests for Mizuna in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or fall. Harvest outer leaves as needed for a cut-and-come-again approach. Mizuna is one of the most cold-tolerant Asian greens.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

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

New London County is in Zone 7a with an average last frost of April 23. Plan your Mizuna 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.