🥦When to Plant Cauliflower in USDA Zone 9b (2026 Guide)
Fussier brassica that wants steady cool weather. Transplant early. Here is the cool-season planting schedule for cauliflower in zone 9b (covering areas like Orlando FL, Tucson AZ). All dates are based on 2026 frost data for your zone.
Start Seeds Indoors
Dec 30
Transplant
Jan 27
Harvest From
Apr 12
Because cauliflower is a cool-season crop, it tolerates light frost and can go out around Jan 27, before zone 9b's average last frost on Feb 10.
- Type: Cool-season
- Method: Transplant
- Days to harvest: 75
- Spacing: 18" apart
- Sun: Full sun
- Zone 9b frost: Feb 10 – Dec 15
- Season length: ~308 days
- Companions: beans, onion, celery
Growing cauliflower in zone 9b
Zone 9b has an average last spring frost around Feb 10 and a first fall frost around Dec 15, giving roughly 308 frost-free growing days. That window comfortably fits cauliflower's 75-day cycle, with room for a second succession planting if you time it right.
Get a head start by sowing seeds indoors around Dec 30, roughly 6 weeks before your last frost. Move the seedlings outside around Jan 27. Give each plant about 18 inches of space in full sun.
Zone 9b specific growing notes
In zone 9b (Orlando FL, Tucson AZ), your 308-day growing season means cauliflower should be one of your first spring plantings. Cool-season crops thrive in the mild part of your growing window. Monitor soil temperature — cauliflower germinates best when soil is 40-75°F.
Your first fall frost around Dec 15 means your last possible harvest is roughly late Dec. For a continuous supply, consider succession planting every 2-3 weeks from Jan 27 through mid-season.
Pro tip for cauliflower
Blanch heads by gathering outer leaves and tying them loosely over the developing curd with string or a rubber band when it reaches 2-3 inches across. This keeps the curd snowy white and prevents bitterness.
Troubleshooting cauliflower
Buttoning—forming tiny, unusable heads prematurely—is caused by temperature swings, drought stress, or root-bound seedlings. Transplant on time (not late), keep soil consistently moist, and choose stress-tolerant varieties.
Growing cauliflower in containers
One plant per 5-gallon pot, but cauliflower is the most challenging brassica for containers. It demands perfectly steady cool temperatures, no check in growth, and consistent moisture from transplant to harvest.
Can you plant cauliflower twice a year?
Yes—and fall cauliflower often outperforms spring-planted. Start seeds indoors in early July in zones 5+ and transplant by early August. Heads mature in September-October cooling weather with fewer pest issues.
Frequently asked questions
When should I plant cauliflower in zone 9b?
Transplant around Jan 27. If starting from seed indoors, sow around Dec 30. Because cauliflower is a cool-season crop, it tolerates light frost and can go out around Jan 27, before zone 9b's average last frost on Feb 10.
How long does cauliflower take to grow in zone 9b?
About 75 days from transplanting to first harvest. A Jan 27 planting in zone 9b is typically ready to pick from around Apr 12. Zone 9b has about 308 frost-free days — plenty of time for a second succession planting.
How far apart should I space cauliflower?
Space cauliflower about 18 inches apart in full sun. This gives each plant enough room for roots to spread and leaves to catch sunlight without competing.
What is the best tip for growing cauliflower?
Blanch heads by gathering outer leaves and tying them loosely over the developing curd with string or a rubber band when it reaches 2-3 inches across. This keeps the curd snowy white and prevents bitterness.
What are common problems with cauliflower and how do I fix them?
Buttoning—forming tiny, unusable heads prematurely—is caused by temperature swings, drought stress, or root-bound seedlings. Transplant on time (not late), keep soil consistently moist, and choose stress-tolerant varieties.
Can I grow cauliflower in a container?
One plant per 5-gallon pot, but cauliflower is the most challenging brassica for containers. It demands perfectly steady cool temperatures, no check in growth, and consistent moisture from transplant to harvest.
Can I plant a second crop of cauliflower for fall harvest?
Yes—and fall cauliflower often outperforms spring-planted. Start seeds indoors in early July in zones 5+ and transplant by early August. Heads mature in September-October cooling weather with fewer pest issues.
What grows well next to cauliflower?
Good companion plants for cauliflower are beans, onion, celery. Avoid planting near warm-season crops that compete for space and nutrients. Cauliflower also benefits from crop rotation — do not plant it in the same spot year after year.