When to Plant Kale in Oklahoma
Published: April 24, 2026
Oklahoma gardeners in Zone 7a have a 35-week growing season for kale (March 15 to November 15). Oklahoma's spring and fall windows both work well for kale — some gardeners plant both successions for a long harvest. This guide gives exact dates for Oklahoma based on your local frost calendar.
Kale Planting Dates for Oklahoma
| Start seeds indoors | February 8–15 |
| Last frost (average) | March 15 |
| Transplant outdoors | February 15–25 |
| Direct sow outdoors | February 15–25 |
| Expect first harvest | April 11 – May 1 |
| Fall crop start | September 20–30 |
| Fall harvest | November 14 |
| First fall frost (average) | November 15 |
⚠ Plant kale 3–5 weeks before last frost for spring. Best planted in late summer (6–8 weeks before first fall frost) for fall/winter harvest. Frost sweetens the flavor.
Growing Kale in Oklahoma's Climate
Oklahoma's moderate Zone 7a climate is well-suited to kale 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 kale 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 kale pests to watch for in Oklahoma include Cabbage Worm and Cabbage Looper. The first line of defense is companion planting: Onion and Garlic 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.
Kale Garden Calendar for Oklahoma
| Month | Task | Notes |
|---|---|---|
| January | — | Dormant season |
| February | Transplant outdoors | Soil temp must be 40°F+; nighttime lows above 50°F |
| March | Harden off seedlings | Set seedlings outdoors 1–2 hours daily, increasing gradually |
| April | First harvest window opens | Kale begins producing 55–75 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 kale; cover plants on frost nights |
| December | — | Dormant season |
Kale Growing Tips for Oklahoma Gardeners
- •Harvest outer leaves first using the cut-and-come-again method; the central growing point will produce for months.
- •Kale leaves become sweeter after the first frost as plants convert starches to sugars — wait for cold nights for best flavor.
- •Oklahoma's moderate climate supports succession planting — sow new transplants or seeds every 3 weeks during spring to extend the harvest window into fall.
- •Use floating row covers to block cabbage white butterflies from laying eggs on plants.
Companion Planting for Kale in Oklahoma
In Oklahoma's moderate climate, planting kale with Onion and Garlic helps deter pests and improve soil. Avoid planting near Tomato and Strawberry, which inhibit kale growth through root chemistry or shared pest pressure. See the full kale companion planting guide for the complete list.
Kale 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 kale in Oklahoma?
In Oklahoma (Zone 7a), start kale seeds indoors around February 8–15 and transplant outdoors around February 15–25 — 4 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 kale year-round in Oklahoma?
kale 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 kale varieties grow best in Oklahoma?
For Oklahoma's Zone 7a, consult a local nursery or extension office for kale variety recommendations.
When do I start kale seeds indoors in Oklahoma?
Start kale 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.