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When to Plant Mizuna in USDA Zone 4b

Zone 4b Zone 4b April

Your April planting checklist for Zone 4b

April rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Zone 4b.

Avg. last frost May 5
Avg. first frost October 6
  1. Seed mizuna outdoors

    Mark the row. Birds and stray feet both have opinions about unmarked beds.

To set up a strong May, finish these tasks
  • Transplants going out: mizuna
Download your personalised Zone 4b planting plan →

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.

In Zone 4b, the average last spring frost is around May 1 and the first fall frost is around October 3, giving you a growing season of approximately 155 days.

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Zone 4b Moderate season
155 days
Last Spring Frost May 1
155 growing days
First Fall Frost October 3

Mizuna Planting Timeline — Zone 4b

Where Is USDA Zone 4b?

The map below highlights the states that contain Zone 4b. Click any state to see the Mizuna planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Mizuna Planting Calendar — Zone 4b

Activity When Date Range
Start Indoors March 20 Mar 20 – Apr 3
Transplant Outdoors May 1 May 1 – May 15
Direct Sow April 24 Apr 24 – May 15
Harvest June 5 Jun 5 – Jul 3
Fall Sowing July 11 Jul 11 – Jul 25

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

Month-by-Month Timeline

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

Free Zone 4b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4b with start dates, transplant windows, and harvest times.

Instant PDF download. No spam, unsubscribe any time.

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Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

Days to Maturity

30–45 days

Soil pH

6 – 7.5

Zone Temperature Range

°F to °F average annual minimum

Growing Season

155 days (Zone average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing6 inches apart
Row Spacing12 inches between rows

Succession Planting Mizuna in Zone

6
successive plantings in Zone 's ~155-day season

Sow every 3.4 weeks for continuous harvest throughout the season.

Growing Tips for Mizuna in Zone

Zone has a short growing season (~155 days). Start Mizuna indoors early and use season-extension techniques like row covers and cold frames.

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
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Saving Mizuna Seeds

Recommended for Your Garden

🌱
Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

🏷️
Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

Related Plants

Frequently Asked Questions

When should I plant Mizuna in Zone 4b?

In Zone 4b, plan your Mizuna planting around the average last frost date of May 1. Start seeds indoors around March 20. Direct sow outdoors around April 24. Transplant seedlings around May 1.

Can Mizuna grow in Zone 4b?

Yes, Mizuna can grow well in Zone 4b, hardy in USDA zones 3a through 11b. Zone 4b has a growing season of approximately 155 days, which is sufficient for Mizuna (30-45 days to maturity).

When can I harvest Mizuna in Zone 4b?

In Zone 4b, expect to harvest Mizuna from June 5 – July 3. Mizuna takes 30-45 days from planting to harvest.

What is the last frost date for Zone 4b?

The average last spring frost in Zone 4b is around May 1, and the first fall frost is around October 3. This gives a growing season of approximately 155 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Mizuna?

Good companion plants for Mizuna include Lettuce, Spinach, Radish. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Your Free Printable Garden Planner

A 24-page printable planner tailored to your zone. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.

Sources & credits

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