When to Plant Brussels Sprouts in USDA Zone 4b
Your May gardening checklist
Welcome to May in Zone 4b. These are the moves that will have the biggest impact on your growing season.
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Plant out brussels sprouts
Frost risk is low now in Zone 4b. If you've been covering beds overnight, you can stop.
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Seed brussels sprouts outdoors
Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.
Looking ahead to June
- Starting indoors: brussels sprouts
Brussels sprouts are a cold-hardy brassica that produces miniature cabbage-like heads along a tall stalk. Flavor improves after a light frost.
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.
Brussels Sprouts 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 Brussels Sprouts planting schedule for that location.
Brussels Sprouts 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 | July 31 | Jul 31 – Sep 25 |
| Fall Sowing | July 11 | Jul 11 – Jul 25 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| 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
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
Days to Maturity
90–130 days
Soil pH
6 – 7.5
Zone Temperature Range
°F to °F average annual minimum
Growing Season
155 days (Zone average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 15 inches apart |
| Row Spacing | 24 inches between rows |
Growing Tips for Brussels Sprouts in Zone
Zone has a short growing season (~155 days). Start Brussels Sprouts indoors early and use season-extension techniques like row covers and cold frames.
Start seeds indoors 12-14 weeks before first fall frost. Stake tall plants to prevent toppling. Remove lower leaves as sprouts develop to improve air circulation.
Companion Planting
Good Companions
Avoid Planting Near
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Saving Brussels Sprouts Seeds
Recommended for Your Garden
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Keep your garden organized with durable, weather-resistant plant labels.
Related Plants
Brussels Sprouts in Other Zones
Brussels Sprouts 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 Brussels Sprouts in Zone 4b?
In Zone 4b, plan your Brussels Sprouts 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 Brussels Sprouts grow in Zone 4b?
Yes, Brussels Sprouts can grow well in Zone 4b, hardy in USDA zones 2a through 10b. Zone 4b has a growing season of approximately 155 days, which is sufficient for Brussels Sprouts (90-130 days to maturity).
When can I harvest Brussels Sprouts in Zone 4b?
In Zone 4b, expect to harvest Brussels Sprouts from July 31 – September 25. Brussels Sprouts takes 90-130 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 Brussels Sprouts?
Good companion plants for Brussels Sprouts include Carrots, Celery, Dill, Sage. 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.