When to Plant Cauliflower in Hamilton County, OH
Cauliflower is a cool-season brassica that produces dense white, purple, or green heads called curds. It is more finicky than broccoli but rewards with a mild, nutty flavor.
Hamilton County, Ohio is in USDA Zone 6a. The average last spring frost is April 16 and the first fall frost is October 21, giving you a growing season of approximately 188 days.
At an elevation of 735 feet, Hamilton County receives approximately 38.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Cauliflower during the growing season.
Hamilton County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.3
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Cauliflower Planting Timeline — Hamilton County, OH
Cauliflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Direct Sow | April 2 | Apr 2 – Apr 23 |
| Fall Sowing | August 12 | Aug 12 – Aug 26 |
| Harvest | June 11 | Jun 11 – Aug 13 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
High — keep soil consistently moist
Days to Maturity
55–100 days
Soil pH
6 – 7
USDA Zone
Zone 6a
Growing Season
188 days
Growing Tips for Hamilton County
Start seeds indoors 6 weeks before transplanting. Blanch white varieties by tying outer leaves over the head. Provide consistent moisture and avoid temperature extremes.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Cauliflower in Other Locations
Frequently Asked Questions
When should I plant Cauliflower in Hamilton County, OH?
Hamilton County is in Zone 6a with an average last frost of April 16. Plan your Cauliflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hamilton County, OH?
Hamilton County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is April 16 and first fall frost is October 21.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Hamilton County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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