When to Plant Mizuna in USDA Zone 4b
July in the garden — Zone 4b
Each item below is timed to Zone 4b's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Start harvesting mizuna
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
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Sow mizuna for an autumn harvest
Keep young seedlings shaded and moist in summer heat. A row of taller crops works as natural shade.
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.
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.
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
| Month | Activities |
|---|---|
| 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.
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 -20°F average annual minimum
Growing Season
155 days (Zone 4b average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 6 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Mizuna in Zone 4b
Sow every 3.4 weeks for continuous harvest throughout the season.
Growing Tips for Mizuna in Zone 4b
Zone 4b 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
The Gardener's Encyclopedia to Companion Planting
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
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Saving Mizuna Seeds
Recommended for Your Garden
Full-spectrum LED lights for starting seeds indoors when daylight is limited.
Warm soil for faster germination of heat-loving crops like tomatoes and peppers.
Protect plants from frost, wind, and pests while letting light and water through.
Related Plants
Mizuna in Other Zones
Mizuna by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
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 Zone 4b Garden Planner — Free
A 22-page printable planner tailored to Zone 4b. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.