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When to Plant Mitsuba in USDA Zone 4a

Zone 4a Zone 4a May

What to do in May

May is a pivotal month for Zone 4a gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 13
Avg. first frost September 28
  1. Plant out mitsuba

    Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.

  2. Direct-sow mitsuba

    Your soil is warming°F — warm enough for these to germinate without babying.

To set up a strong June, finish these tasks
  • Starting indoors: mitsuba
Download your personalised Zone 4a planting plan →

Mitsuba (Japanese parsley) is a shade-loving herb with trefoil leaves and a mild celery-parsley flavor. It is essential in Japanese cuisine for soups, salads, and garnishes.

In Zone 4a, the average last spring frost is around May 6 and the first fall frost is around September 28, giving you a growing season of approximately 145 days.

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Zone 4a Short season
145 days
Last Spring Frost May 6
145 growing days
First Fall Frost September 28

Mitsuba Planting Timeline — Zone 4a

Where Is USDA Zone 4a?

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

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

Mitsuba Planting Calendar — Zone 4a

Activity When Date Range
Start Indoors March 25 Mar 25 – Apr 8
Transplant Outdoors April 29 Apr 29 – May 13
Direct Sow April 29 Apr 29 – May 20
Harvest June 24 Jun 24 – Aug 19
Fall Sowing July 6 Jul 6 – Jul 20

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

Month-by-Month Timeline

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

Free Zone 4a Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4a 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

50–70 days

Soil pH

6 – 7

Zone Temperature Range

°F to °F average annual minimum

Growing Season

145 days (Zone average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing8 inches apart
Row Spacing12 inches between rows

Succession Planting Mitsuba in Zone

3
successive plantings in Zone 's ~145-day season

Sow every 5.7 weeks for continuous harvest throughout the season.

Growing Tips for Mitsuba in Zone

Zone has a short growing season (~145 days). Start Mitsuba indoors early and use season-extension techniques like row covers and cold frames.

Direct sow or start indoors in partial shade. Mitsuba prefers cool, moist conditions. Harvest outer stems as needed. Self-sows readily in shaded garden areas.

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Saving Mitsuba 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.

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Frequently Asked Questions

When should I plant Mitsuba in Zone 4a?

In Zone 4a, plan your Mitsuba planting around the average last frost date of May 6. Start seeds indoors around March 25. Direct sow outdoors around April 29. Transplant seedlings around April 29.

Can Mitsuba grow in Zone 4a?

Yes, Mitsuba can grow well in Zone 4a, hardy in USDA zones 4a through 9b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Mitsuba (50-70 days to maturity).

When can I harvest Mitsuba in Zone 4a?

In Zone 4a, expect to harvest Mitsuba from June 24 – August 19. Mitsuba takes 50-70 days from planting to harvest.

What is the last frost date for Zone 4a?

The average last spring frost in Zone 4a is around May 6, and the first fall frost is around September 28. This gives a growing season of approximately 145 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Mitsuba?

Good companion plants for Mitsuba include Lettuce, Spinach. 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: May 2026.

Sources & credits

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