Blog

When to Plant Mizuna in Baltimore County, MD

Baltimore County, Maryland Zone 7b May

This month in Baltimore County, Maryland

Here's what deserves your attention in Baltimore County, Maryland this month. Everything below is tailored to Zone 7b and timed around your local frost dates.

Avg. last frost April 3
Avg. first frost November 6
Soil temp (4") 68°F
Watering Low
Pest pressure Moderate
Daylight 14.2 hrs
  1. Sow mizuna in trays indoors

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. It's harvest week for mizuna

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

To set up a strong June, finish these tasks
  • 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.

Baltimore County, Maryland is in USDA Zone 7b. The average last spring frost is April 3 and the first fall frost is November 6, giving you a growing season of approximately 217 days.

At an elevation of 641 feet, Baltimore County receives approximately 49.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Mizuna during the growing season.

Baltimore County, MD (Zone 7b) Long season
217 days
Last Spring Frost April 3
217 growing days
First Fall Frost November 6

Baltimore County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (155 days to spare)
Start indoors: Feb 21 Transplant: Mar 28 🍅 Harvest: May 2 – May 30
Recommended (50%) ✓ Fits season (154 days to spare)
Start indoors: Feb 27 Transplant: Apr 3 🍅 Harvest: May 8 – Jun 5
Safe Start (90%) ✓ Fits season (156 days to spare)
Start indoors: Mar 12 Transplant: Apr 16 🍅 Harvest: May 21 – Jun 18

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 Baltimore County

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

Soil pH

Your soil pH (5.7–7.0) overlaps with Mizuna's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.1%). 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

8
successive plantings in your 217-day season

Sow every 3.4 weeks. Last sowing by Sep 22 to harvest before frost.

For a dedicated fall crop, sow by Aug 28.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 96 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 3.9" 0" ❄️ Dormant
Feb 3.2" 0" ❄️ Dormant
Mar 3.8" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 4.7" 0" ✅ Rainfall sufficient
Jun 4.3" 4.9" 0" ✅ Rainfall sufficient
Jul 4.3" 5.5" 0" ✅ Rainfall sufficient
Aug 4.3" 4.7" 0" ✅ Rainfall sufficient
Sep 4.3" 4.2" 0.1" 💧 Light watering
Oct 4.3" 3.5" 0.8" 💧 Light watering
Nov 4.3" 3.8" 0.5" 💧 Light watering
Dec 3.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Baltimore 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 ~741 GDD — county provides 4,285 GDD Excellent fit

Mizuna Planting Timeline — Baltimore County, MD

Mizuna Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow March 20 Mar 20 – Apr 10
Harvest May 8 May 8 – Jun 5
Fall Sowing August 28 Aug 28 – Sep 11

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

30–45 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

217 days in Baltimore County

Growing Tips for Mizuna in Baltimore County

Direct sow Mizuna outdoors after April 03 in Baltimore County when soil has warmed and frost danger has passed.

Your generous 217.0-day season in Baltimore 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 Baltimore County, MD?

Baltimore County is in Zone 7b with an average last frost of April 3. Plan your Mizuna planting based on this frost date — see the calendar above for exact timing.

What planting zone is Baltimore County, MD?

Baltimore County, Maryland is in USDA Hardiness Zone 7b. The average last spring frost is April 3 and first fall frost is November 6.

🌱

Your Baltimore County Garden Planner — Free

A 24-page printable planner built for Baltimore County (Zone 7b). 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 Baltimore County, MD. 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.