GardenBiennial Leafy Green · 21 varieties
Kale
Brassica oleracea Kale Group
Brassicaceae — the same plant family as cabbage, radish, broccoli, cauliflower and 12 more here. Relatives share pests and diseases, which is why rotation plans group by family.
Kale (Brassica oleracea Kale Group) is a biennial leafy green. It wants full sun and pH 6–7.5 soil, with about 1–2 in of water weekly. It matures in about 40–80 days from sowing, or 55 days from setting out a transplant. Watch for aphids and black rot. Below: its full sourced profile from 11 extension sources, plus a planting calendar timed to your frost dates.
Typical dates for zone 6b — set your zone or ZIP for yours. This calendar assumes the crop is direct sown. Timing is a guide from the crop's sourced growth stages; confirm with your local frost dates and extension before you sow.
What we will not put a number on
We do not give a feeding rate for this crop, and that is deliberate rather than a gap. The figures published by extension services are pounds of nitrogen per acre for a production field — they do not convert safely to a raised bed or a pot without knowing your soil test and your fertilizer's analysis, and guessing errs toward burning roots. It is also why every chart you find online disagrees with the next one.
We give watering as a depth per week rather than gallons per plant, because that is how it is actually measured and how the published figures are written. A gallons-per-plant number depends on your spacing, your soil and whether the plant is in a pot — so it would look more precise than it is.
Site & soil
- Sun
- Full sun
- Soil pH
- 6–7.5
- Soil texture
- Loam, Well drained
- Frost tolerance
- Very hardy
No published figure for the temperature that would kill it and a heat limit. We looked — where a number is missing here it is missing from the research, not skipped. The crop’s frost and heat tolerance above still applies.
The plant
- Mature height
- 2–4 ft
- Mature spread
- 1–4 ft
- Growth rate
- Fastest
- Spacing in row
- 12–18 in
- Between rows
- 18–36 in
- Planting depth
- 0.25–0.5 in
- Container size
- 3 gal
- Support
- Self-supportingest
- Grown from
- Direct sow, Transplant
- Sow again for a fall crop
- about 90 days before your first frost
There is no line here for warning signs to watch for. Nobody has published a warning sign for kale. Five university pages were read and not one names something to watch for, so this is empty because the answer is missing, not because kale has none.
Water & feeding
- Water needs
- Moderate
- Water per week
- 1–2 in/wk
- Critical water
- Establishmentest
- Feeding
- Moderate
Timing & fruiting
- Days to maturity
- 40–80 days from seed · 55 days from transplant
- Harvest cues
- Rapid leaf growthest
- Takes cold in the ground down to
- 25 °F
There is no line here for how warm the soil should be for the seed to come up and how many weeks early to start it indoors, because we have no figure to put there. We went looking and wrote down what we read — it is missing on purpose, not because nobody checked.
Planted again for autumn
- South Carolina — Piedmont
- Aug 1 – Sep 30
- South Carolina — Coastal Plain
- Aug 1 – Oct 30
Published by the extension service for its own regions, and quoted here for those regions only — converting them would mean assuming a frost date somewhere else. The chart says when, not whether to sow seed or set out plants, so we do not either. Only South Carolina so far.
- Set plants out by
- late Aug typical · zone 6b
55 days to maturity from setting a plant out — that is what our sources measure for this crop, so this is a date for planting out and not a sowing date, counted back from the first frost above. Not published for anywhere in particular: it is your own frost date and this crop's own figure, which is why it works wherever you are. A days-to-maturity figure is a catalog number for a good season rather than a promise, and a cold month moves it.
Edible parts per source: leaf.
Compiled from the extensions cited below. Which ones actually show up depends on your region — your extension's local list is the last word.
Mixed, strong-smelling plantings make brassicas harder for pests to find — real research, modest effect. Keep mint in a pot.
Dill flowers feed the tiny parasitoid wasps that hunt cabbage worms. Let some of it bloom near the bed.
A trap strip pulls flea beetles off young seedlings. UMN found mixes of three-plus trap species beat any single one.
On the classic chart's companion list for the cabbage family.
On the WVU companion list, with an aphid-magnet reputation. If aphids pile on, pull those plants before they breed.
Old chart pairing; both hold cool-season beds.
Old chart pairing.
Chart canon says no. Nobody's proven why. Cheap to respect.
Flagged on the classic charts, including WVU's. Mechanism murky; the canon is consistent.
Flagged on the classic charts, mechanism murky. Skip the pairing if you've got the space.
Companion pairings from university extensions; badge = how strong the evidence is.
Open one and add it to your garden — it lights up here. The rest of the 21 are in the full list below.
| Variety | Type | Days | Color | What it is known for |
|---|---|---|---|---|
| Beira Portuguese | Portuguese | 60 | Green | Renee's Garden Seeds describes this astakes the cold |
| Black Magic | Lacinato Dino | 65 | Green | High Mowing Organic Seeds describes this astakes the cold |
| Darkibor F1 | Curly | 75 | Green | Johnny's Selected Seeds describes this astakes the cold |
| Dazzling Blue | Lacinato Dino | 60 | Green | Johnny's Selected Seeds describes this astakes the cold |
| Dwarf Blue Curled Vates Heirloom | Curly | 55 | Green | Botanical Interests describes this astakes the cold · takes the heat |
| Dwarf Siberian Heirloom | Siberian | 55 | Green, Purple | Urban Farmer describes this astakes the cold |
| Lacinato Heirloom | Lacinato Dino | 60 | Green | High Mowing Organic Seeds describes this astakes the cold |
| Mamba F1 | Lacinato Dino | 60 | Green | High Mowing Organic Seeds describes this astakes the cold |
| Premier Heirloom | Premier | 60 | Green | Urban Farmer describes this astakes the cold |
| Prizm F1 | Curly | 50–60 | Green | Territorial Seed Company describes this astakes the cold |
| Ragged Jack Heirloom | Red Russian | 50 | Green, Red | Hudson Valley Seed Company describes this astakes the cold |
| Rainbow Lacinato | Lacinato Dino | 61 | Green, Purple | Fedco Seeds describes this astakes the cold |
| Red Russian Heirloom | Red Russian | 50 | Green, Purple | Johnny's Selected Seeds describes this astakes the cold |
| Redbor F1 | Curly | 55 | Red, Purple | Johnny's Selected Seeds describes this astakes the cold |
| Scarlet | Curly | 55 | Red, Purple | Johnny's Selected Seeds describes this astakes the cold |
| Siberian Heirloom | Siberian | 60 | Green | High Mowing Organic Seeds describes this astakes the cold |
| Starbor F1 | Curly | 55 | Green | Johnny's Selected Seeds describes this astakes the cold |
| Toscano Heirloom | Lacinato Dino | 55 | Green | Johnny's Selected Seeds describes this astakes the cold · takes the heat |
| White Russian | Siberian | 50 | Green | Johnny's Selected Seeds describes this astakes the cold |
| Wild Garden Kale Mix | 50 | Green, Red, Purple | Nichols Garden Nursery describes this astakes the cold | |
| Winterbor F1 | Curly | 60 | Green | Johnny's Selected Seeds describes this astakes the cold |
- Clemson Cooperative Extension, Home & Garden Information Center
- Harvest to Table
- NC State Extension
- Penn State Extension
- University of Maryland Extension
- University of Minnesota Extension
- Utah State University Extension
- West Virginia University Extension
We compile bare facts from these university-extension and horticultural sources, never copied prose. 17 of the 21 values on this page carry a citation. The rest are marked est; hover one and it says why — either nobody publishes a figure we could point at, or a person set it and attached no source. Figures vary with climate and seed source; confirm with your local extension before you buy.
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