Temperature / 66–70°F / Kale
Kale at 66–70°F: 12 days
66–70°F spans the standard 68°F baseline — most published timings assume this range. Target pH 3.40 · default salt 2.50%.
Temperature & timing
Most published recipes assume a 68 °F kitchen. Enter the base days for your recipe and the temperature you actually have — we return the adjusted fermentation time.
Safety at 66–70°F
Standard temperate ferment zone. Ideal for most kitchens. LAB dominance immediate. Pathogen risk minimal. NCHFP-recommended baseline for home ferments. Slightly below 68°F reference gives a modest speed reduction.
At this range: Default recommendation. Works for every lacto-ferment style. First-time fermenters should aim for this range. Visible bubbling activity starts day 2-3 and is obviously vigorous.
About kale
A sturdy brassica leaf that ferments into a robust, earthy kraut. Tougher and lower-water than cabbage, kale is usually destemmed and blended with shredded cabbage or salted firmly on its own. The thick leaves keep good texture and don't collapse the way tender greens do.
Technique
Strip leaves from the stems and chop or chiffonade. Salt at 2.5% of leaf weight and massage 5-8 minutes until wilted and weeping — the lower water content needs more massaging than cabbage. Pack tightly below the brine and ferment 7-18 days at 65-72°F. Blends well 50/50 with green cabbage.
- Time @ 68°F
- 12.0 days
- Time @ 66–70°F
- 12 days
- Water content
- 84%
Kale at other temperatures
Other leafy ferments at 66–70°F
- Green Cabbage — 14 days
- Napa Cabbage — 5.0 days
- Cauliflower — 10 days
- Brussels Sprouts — 10 days
Sources
For educational use only. Consult your local food safety authority for commercial production. Last verified 2026-09-06.
Frequently asked questions
How long does kale take to ferment at 66–70°F?
About 12 days at 66–70°F (18.89–21.11°C) — 1× the speed of the 12.0-day baseline at 68°F. Start tasting from day 5 regardless of temperature; target pH is 3.40 or below.
Is 66–70°F safe for fermenting kale?
Standard temperate ferment zone. Ideal for most kitchens. LAB dominance immediate. Pathogen risk minimal. NCHFP-recommended baseline for home ferments. Slightly below 68°F reference gives a modest speed reduction.
What salt percentage for kale at this temperature?
Salt percentage doesn't change with temperature — 2.50% by weight is still the default for kale (workable range 2.00%–3.00%). Temperature changes speed, not the salt ratio.
The kit for fermenting kale at 66–70°F
A short, honest kit for lacto-fermentation. The scale is the one that matters most — everything here is by weight.
- Digital kitchen scale (0.1 g)Salt % is by weight, not volume — a 0.1 g scale is what makes the math above accurate.View on Amazon →
- Glass fermentation weightsKeep vegetables submerged under the brine line so they ferment safely without mould.View on Amazon →
- Airlock fermentation lidsLet CO₂ escape while keeping oxygen out — wide-mouth lids that fit standard jars.View on Amazon →
- Wide-mouth mason jarsThe workhorse vessel for kraut, kimchi and brine pickles — 1 qt and ½ gal sizes.View on Amazon →
- Pickling / fine sea saltPure salt with no iodine or anti-caking agents, which can cloud brine and inhibit fermentation.View on Amazon →
- Stoneware fermentation crockFor scaling past the jar — a water-sealed crock for 5 L+ batches with built-in weights.View on Amazon →
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