When to Plant Cauliflower in Oklahoma
Published: April 24, 2026
Oklahoma gardeners in Zone 7a have a 35-week growing season for cauliflower (March 15 to November 15). Oklahoma's spring and fall windows both work well for cauliflower — some gardeners plant both successions for a long harvest. This guide gives exact dates for Oklahoma based on your local frost calendar.
Cauliflower Planting Dates for Oklahoma
| Start seeds indoors | February 8–15 |
| Last frost (average) | March 15 |
| Transplant outdoors | February 22–March 4 |
| Expect first harvest | April 18 – June 2 |
| Fall crop start | September 6–16 |
| Fall harvest | October 31 |
| First fall frost (average) | November 15 |
⚠ Start cauliflower indoors 4–6 weeks before last frost. Transplant 2–4 weeks before last frost. Needs consistent moisture and cool temps — bolts in heat above 75°F.
Growing Cauliflower in Oklahoma's Climate
Oklahoma's moderate Zone 7a climate is well-suited to cauliflower with minimal special accommodation. The standard transplant calendar works as written, and harvest windows line up with what seed packets recommend without adjustment.
Succession planting extends your cauliflower harvest significantly in Oklahoma. A second planting 3 to 4 weeks after the first gives you a backup in case of pest pressure and extends the total harvest window into early fall.
Common cauliflower pests to watch for in Oklahoma include Cabbage Worm and Cabbage Looper. The first line of defense is companion planting: Onion and Celery planted nearby discourage several of these pests by confusing host-plant identification or repelling adults before they can lay eggs. Weekly garden walks in the early morning catch problems when they're still manageable.
Cauliflower Garden Calendar for Oklahoma
| Month | Task | Notes |
|---|---|---|
| January | — | Dormant season |
| February | Transplant outdoors | Soil temp must be 45°F+; nighttime lows above 50°F |
| March | Harden off seedlings | Set seedlings outdoors 1–2 hours daily, increasing gradually |
| April | First harvest window opens | Cauliflower begins producing 55–100 days after transplant |
| May ← | Watch for bolting | Harvest promptly; spring heat arrives quickly |
| June | — | Dormant season |
| July | — | Dormant season |
| August | — | Dormant season |
| September | Fall crop planting | Transplant or direct sow for fall harvest before frost |
| October | — | Dormant season |
| November | First frost approaches | Harvest remaining cauliflower; cover plants on frost nights |
| December | — | Dormant season |
Cauliflower Growing Tips for Oklahoma Gardeners
- •Blanch white varieties by tying outer leaves over the head when it reaches egg-size — prevents yellowing from sun exposure.
- •Keep soil evenly moist — drought stress causes small, bitter 'buttoning' heads instead of full curds.
- •Oklahoma's moderate climate supports succession planting — sow new transplants or seeds every 3 weeks during spring to extend the harvest window into fall.
- •Plant fall crops in mid-July to mid-August for October harvest; fall cauliflower is usually larger and sweeter than spring.
Companion Planting for Cauliflower in Oklahoma
In Oklahoma's moderate climate, planting cauliflower with Onion and Celery helps deter pests and improve soil. Avoid planting near Tomato and Strawberry, which inhibit cauliflower growth through root chemistry or shared pest pressure. See the full cauliflower companion planting guide for the complete list.
Cauliflower Planting Dates by City in Oklahoma
Top cities in Oklahoma — select for city-level frost dates and planting calendars.
Frequently Asked Questions
When should I plant cauliflower in Oklahoma?
In Oklahoma (Zone 7a), start cauliflower seeds indoors around February 8–15 and transplant outdoors around February 22–March 4 — 3 weeks before the state's average last frost of March 15.
What is the last frost date in Oklahoma?
Oklahoma's average last frost date is March 15 in the state's most common Zone 7a. Frost dates vary by city — higher elevations and northern counties run 1 to 3 weeks later than the state average. See the city list below for city-level frost dates.
Can I grow cauliflower year-round in Oklahoma?
cauliflower is a cool-season crop in Oklahoma, with spring and fall windows. Summer heat bolts the plants before they can produce a harvestable crop. Succession planting every 2–3 weeks stretches the harvest window.
What cauliflower varieties grow best in Oklahoma?
For Oklahoma's Zone 7a, consult a local nursery or extension office for cauliflower variety recommendations.
When do I start cauliflower seeds indoors in Oklahoma?
Start cauliflower seeds indoors in Oklahoma around February 8–15, which is 5 weeks before the state's average last frost of March 15. Use grow lights and keep soil temperatures at 70–75°F for fastest germination.