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When to Plant Mizuna in USDA Zone 9b

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 9b, the average last spring frost is around January 25 and the first fall frost is around December 20, giving you a growing season of approximately 329 days.

Zone 9b Year-round
329 days
Last Spring Frost January 25
329 growing days
First Fall Frost December 20

Mizuna Planting Timeline — Zone 9b

Where Is USDA Zone 9b?

The map below highlights the states that contain Zone 9b. 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 9b

Activity When Date Range
Start Indoors December 28 Dec 28 – Jan 11
Transplant Outdoors January 25 Jan 25 – Feb 8
Direct Sow January 4 Jan 4 – Jan 25
Fall Sowing October 25 Oct 25 – Nov 8
Harvest March 1 Mar 1 – Mar 29

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

Month-by-Month Timeline

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

Free Zone 9b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 9b 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

30–45 days

Soil pH

6 – 7.5

Zone Temperature Range

25°F to 30°F average annual minimum

Growing Season

329 days (Zone 9b average)

Planting Specifications

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

Growing Tips for Zone 9b

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

Level Up Your Garden

Saving Mizuna Seeds

Recommended for Your Garden

☀️
Garden Shade Cloth $15-35

Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.

🌱
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.

Related Plants

Frequently Asked Questions

When should I plant Mizuna in Zone 9b?

In Zone 9b, plan your Mizuna planting around the average last frost date of January 25. Start seeds indoors around December 28. Direct sow outdoors around January 4. Transplant seedlings around January 25.

Can Mizuna grow in Zone 9b?

Yes, Mizuna can grow well in Zone 9b, hardy in USDA zones 3a through 11b. Zone 9b has a growing season of approximately 329 days, which is sufficient for Mizuna (30-45 days to maturity).

When can I harvest Mizuna in Zone 9b?

In Zone 9b, expect to harvest Mizuna from March 1 – March 29. Mizuna takes 30-45 days from planting to harvest.

What is the last frost date for Zone 9b?

The average last spring frost in Zone 9b is around January 25, and the first fall frost is around December 20. This gives a growing season of approximately 329 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.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 9b, track your crops, and plan your garden season from seed to harvest.

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Free download. Plan your entire garden season in minutes.

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.