When to Plant Brussels Sprouts in USDA Zone 9b
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 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.
Brussels Sprouts 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 Brussels Sprouts planting schedule for that location.
Brussels Sprouts 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 |
| Harvest | April 26 | Apr 26 – Jun 21 |
| Fall Sowing | October 25 | Oct 25 – Nov 8 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Transplant Outdoors Direct Sow |
| February | Transplant Outdoors |
| March | — |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| 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.
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
25°F to 30°F average annual minimum
Growing Season
329 days (Zone 9b 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 9b
Zone 9b offers a long growing season (~329 days). You can plant Brussels Sprouts earlier and may get multiple harvests.
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
Level Up Your Garden
Saving Brussels Sprouts Seeds
Recommended for Your Garden
Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
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 9b?
In Zone 9b, plan your Brussels Sprouts 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 Brussels Sprouts grow in Zone 9b?
Yes, Brussels Sprouts can grow well in Zone 9b, hardy in USDA zones 2a through 10b. Zone 9b has a growing season of approximately 329 days, which is sufficient for Brussels Sprouts (90-130 days to maturity).
When can I harvest Brussels Sprouts in Zone 9b?
In Zone 9b, expect to harvest Brussels Sprouts from April 26 – June 21. Brussels Sprouts takes 90-130 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 Brussels Sprouts?
Good companion plants for Brussels Sprouts include Carrots, Celery, Dill, Sage. These companions can help with pest control, pollination, and nutrient sharing.
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