Lacto-fermenting fennel: 2.50% salt, 10.0days at 68 °F
The crisp bulb ferments into a softly anise-scented pickle that keeps a satisfying crunch. Fennel's licorice notes mellow as it sours, making it a favorite in Italian giardiniera and as a foil for rich foods. The fronds can be fermented along with the bulb for extra aroma.
Salt calculator
Enter your vegetable weight and a salt percentage. We return the exact salt mass in grams, plus teaspoons for each common grain.
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Grain matters: one teaspoon of Diamond Crystal weighs half as much as one teaspoon of fine sea salt. Weigh in grams when you can.
Trim the stalks, halve the bulb, and slice 3-5mm or cut into wedges. Cover with a 2.5% salt brine (25g salt per liter); add a few fennel seeds or a strip of lemon peel if desired. Weigh below the brine and ferment 7-14 days at 65-72°F, then refrigerate while still crisp.
2.50% by weight is the default for fennel (workable range 2.00%–3.00%). For 1000g fennel, that's 25.0g salt. Use non-iodised salt and weigh in grams — teaspoon equivalences vary by salt grain. Source: NCHFP (UGA) — fermented brine-pickle method.
How long to ferment fennel?
10.0 days at 68°F (20°C). Cooler kitchens (60-65°F) slow fermentation; warmer kitchens (75-80°F) roughly halve the time per 10°F increase. Start tasting from day 5; target pH 3.60 or below indicates complete primary fermentation.
What's the best technique for fermenting fennel?
Trim the stalks, halve the bulb, and slice 3-5mm or cut into wedges. Cover with a 2.5% salt brine (25g salt per liter); add a few fennel seeds or a strip of lemon peel if desired. Weigh below the brine and ferment 7-14 days at 65-72°F, then refrigerate while still crisp.
What category is fennel for fermentation?
Fennel is a stem vegetable. The crisp bulb ferments into a softly anise-scented pickle that keeps a satisfying crunch. Fennel's licorice notes mellow as it sours, making it a favorite in Italian giardiniera and as a foil for ric… Preferred fermentation style: giardiniera-component, lacto-ferment, brine-pickle.
The kit for fermenting Fennel
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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