When to Plant Cauliflower in Harmon County, OK
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.
Harmon County, Oklahoma is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 5, giving you a growing season of approximately 219 days.
At an elevation of 993 feet, Harmon County receives approximately 34.4 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Cauliflower during the growing season.
Harmon County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
How Much Cauliflower to Grow
For a family of 4, plant approximately 12 cauliflower plants in about 24 sq ft. In Harmon County's 219-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Cauliflower Planting Timeline — Harmon County, OK
Cauliflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 24 | Feb 24 – Mar 10 |
| Transplant Outdoors | March 31 | Mar 31 – Apr 14 |
| Direct Sow | March 17 | Mar 17 – Apr 7 |
| Harvest | May 26 | May 26 – Jul 28 |
| Fall Sowing | August 27 | Aug 27 – Sep 10 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| 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 7b
📆 Growing Season
219 days in Harmon County
Growing Tips for Harmon 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 Harmon County, OK?
Harmon County is in Zone 7b with an average last frost of March 31. Plan your Cauliflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harmon County, OK?
Harmon County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 5.
Your Harmon County Garden Planner — Free
A 22-page printable planner built for Harmon County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.