When to Plant Kale
Planting Window
- Sow or transplant
- Around last frost date
| USDA Zone | Typical Window |
|---|---|
| Zone 5 and colder | April, plus a July-August fall sowing |
| Zone 6-7 | March-April, plus August |
| Zone 8 and south | Fall, winter, and early spring |
Kale is genuinely one of the most cold-hardy crops on this entire site - established plants tolerate hard freezes well into the 20s Fahrenheit or lower, and it's commonly harvested straight through winter in many climates rather than treated as a crop that ends when frost arrives.
Direct Sowing or Transplanting
Kale can be either direct-sown or started indoors and transplanted out later, with either method going into the garden right around your last frost date - it germinates and grows quite reliably in cool soil, without the finicky temperature sensitivity cauliflower shows at the seedling stage of growth.
Frost Sweetens It More Than Most Vegetables on This Site
Kale's flavor improvement after frost is one of the more pronounced examples of this effect covered across this site - cold exposure measurably reduces the slightly bitter edge raw kale can have and adds sweetness, which is why a lot of kale is deliberately grown as a fall crop timed to be harvested after several hard frosts rather than picked in warm weather.
Curly, Lacinato, and Red Russian Handle Cold Differently
Not all kale types are equally cold-hardy - curly kale and Lacinato (dinosaur kale) are both genuinely tough, while Red Russian, though still frost-tolerant, tends to show cold damage a bit sooner than the other two - worth knowing if a planting is specifically intended to be harvested deep into winter rather than just tolerate an occasional frost.
A Genuine Overwintering Crop in Many Zones
Beyond just tolerating occasional frost, established kale plants in many zones survive the entire winter outdoors with minimal protection, sometimes under a layer of row cover or mulch in the coldest stretches, and can be harvested from intermittently through the cold months - a genuinely different relationship with winter than almost any other crop on this site outside of overwintering garlic and certain leek varieties.
Cabbage Worms Are the Most Persistent Pest
Cabbage worms and cabbage loopers are the most persistent pest on kale through the warmer months, chewing ragged holes in leaves faster than almost any other garden pest - floating row cover kept on from transplanting onward is the most reliable non-spray fix, since it physically blocks the white butterflies from laying eggs on the leaves in the first place.
Zone boundaries follow the USDA Plant Hardiness Zone Map (2023 revision); frost windows reflect NOAA/NCEI climate normals. Both are typical historical ranges, reviewed annually - not a forecast or a guarantee for any single year. See Methodology & Sources.
Frequently Asked Questions
Can kale really survive a hard freeze, or does it just look like it can?
It genuinely can - established kale plants routinely tolerate temperatures well into the 20s Fahrenheit and sometimes colder with only minor leaf damage, which is a meaningfully higher cold tolerance than most other leafy greens or brassicas on this site show.
Is fall-planted kale really better than spring-planted kale, or is that just personal preference?
There's a real mechanism behind the preference, not just taste opinion - fall-grown kale that experiences several frosts has measurably converted more starch to sugar than kale harvested in warm weather, so the sweetness difference gardeners report has a genuine physiological basis.
Is a young kale transplant just as cold-hardy as an established plant going into its first hard freeze?
No - cold tolerance builds as a plant matures and experiences gradually dropping temperatures through fall, so a transplant that's still young when an early cold snap hits handles it worse than the same plant would after a full season of growth. Established, fall-hardened kale is what reliably tolerates the 20s Fahrenheit; a small transplant caught by a surprise early frost is more vulnerable and worth covering if a hard freeze is forecast unusually early.