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When to Plant Tatsoi in USDA Zone 4a

Zone 4a Zone 4a May

Your May game plan for Zone 4a

We've pulled the most time-sensitive tasks for Zone 4a this May and put them front and centre. Tackle them in order.

Avg. last frost May 13
Avg. first frost September 28
  1. Time to transplant tatsoi

    Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.

  2. Outdoor sowing time: tatsoi

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

To set up a strong June, finish these tasks
  • Starting indoors: tatsoi
  • First harvests: tatsoi
Send me my free Zone 4a Planting Guide →

Tatsoi is a compact Asian green forming beautiful rosettes of dark, spoon-shaped leaves with a mild mustard flavor. It is extremely cold-hardy and versatile.

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

Tatsoi 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 Tatsoi planting schedule for that location.

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

Tatsoi Planting Calendar — Zone 4a

Activity When Date Range
Start Indoors March 25 Mar 25 – Apr 8
Transplant Outdoors May 6 May 6 – May 20
Direct Sow April 29 Apr 29 – May 20
Harvest June 10 Jun 10 – Jul 15
Fall Sowing July 6 Jul 6 – Jul 20

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 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.

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Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

Days to Maturity

35–50 days

Soil pH

6 – 7.5

Zone Temperature Range

°F to °F average annual minimum

Growing Season

145 days (Zone average)

Planting Specifications

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

Succession Planting Tatsoi in Zone

4
successive plantings in Zone 's ~145-day season

Sow every 4 weeks for continuous harvest throughout the season.

Growing Tips for Tatsoi in Zone

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

Direct sow in spring or fall. Tatsoi tolerates frost down to 15F. Harvest outer leaves or cut whole rosettes. Excellent in salads, stir-fries, or lightly wilted.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
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Saving Tatsoi 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.

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Garden Plant Markers $6-12

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

Related Plants

Frequently Asked Questions

When should I plant Tatsoi in Zone 4a?

In Zone 4a, plan your Tatsoi 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 May 6.

Can Tatsoi grow in Zone 4a?

Yes, Tatsoi can grow well in Zone 4a, hardy in USDA zones 2a through 11b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Tatsoi (35-50 days to maturity).

When can I harvest Tatsoi in Zone 4a?

In Zone 4a, expect to harvest Tatsoi from June 10 – July 15. Tatsoi takes 35-50 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 Tatsoi?

Good companion plants for Tatsoi 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: May 2026.

Sources & credits

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