When to Plant Cauliflower in Knox 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.
Knox County, Ohio is in USDA Zone 5b. The average last spring frost is April 29 and the first fall frost is October 15, giving you a growing season of approximately 169 days.
At an elevation of 861 feet, Knox County receives approximately 33 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Cauliflower during the growing season.
Knox County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.7
Drainage
Well Drained
How Much Cauliflower to Grow
For a family of 4, plant approximately 12 cauliflower plants in about 24 sq ft. In Knox County's 169-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Monthly Watering Guide for Cauliflower
Cauliflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Cauliflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3" | 1.3" | 💧 Light watering |
| May | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Jul | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Aug | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Sep | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Oct | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Nov | — | 2.1" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Knox County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cauliflower Planting Timeline — Knox County, OH
Cauliflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 25 | Mar 25 – Apr 8 |
| Transplant Outdoors | April 29 | Apr 29 – May 13 |
| Direct Sow | April 15 | Apr 15 – May 6 |
| Harvest | June 24 | Jun 24 – Aug 26 |
| Fall Sowing | August 6 | Aug 6 – Aug 20 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| 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
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
169 days in Knox County
Growing Tips for Knox 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
Check more plant combinations with our Companion Planting Checker →
Cauliflower in Other Locations
Frequently Asked Questions
When should I plant Cauliflower in Knox County, OH?
Knox County is in Zone 5b with an average last frost of April 29. Plan your Cauliflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, OH?
Knox County, Ohio is in USDA Hardiness Zone 5b. The average last spring frost is April 29 and first fall frost is October 15.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Knox County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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