What to ferment each month
Month by month, what's in season and what you can start with it. For the Northern Hemisphere, plus what has no season and how the time of year changes your kitchen.
6 min read First steps Reviewed October 26, 2026 7 facts, each with its source
How to read the calendar
Fermenting starts at the market. The guides call for fresh, in-season produce1, and the sooner it reaches the jar, the better: sauerkraut is started 24 to 48 hours after the cabbage is harvested2, and pickles within 24 hours of picking3. What's in season is fresher, tastes of more and costs less.
The calendar is for the Northern Hemisphere: it works for most of the US and for Spain. It comes from the months of each Fervida ingredient and the recipes that use them. Take it as a guide: a month earlier or later, depending on where you live, is normal.
Month by month
| Month | In season | To start |
|---|---|---|
| January | Green and red cabbage, napa cabbage, cauliflower, turnip, daikon, leek, lemon | Homemade sauerkraut, napa cabbage kimchi, kkakdugi, preserved lemons, beet kvass |
| February | Savoy cabbage, Brussels sprouts, broccoli, fennel, celery, lemon | Fennel and lemon sauerkraut, white kimchi, cauliflower with turmeric, fermented beets |
| March | Last of the cabbage, radish, asparagus, green onion, leek | Red cabbage sauerkraut, fermented radishes, fermented asparagus, green onion kimchi |
| April | Radish, asparagus, green onion, fennel, celery | Fermented asparagus, green onion kimchi, strawberry water kefir |
| May | Beet, radish, asparagus, fresh dill, grape leaves | Fermented radishes, fermented asparagus, strawberry water kefir |
| June | Cucumber, green beans, zucchini, dill, grape leaves | Dill pickles, oi sobagi, green beans with garlic, berry kombucha |
| July | Cucumber, bell pepper, chilies, jalapeño, habanero, serrano, tomatillo | Fermented bell peppers, jalapeño hot sauce, sriracha, salsa verde, habanero mango |
| August | Bell pepper, chilies, green tomato, tomatillo, pear | Giardiniera, green tomatoes, Tabasco-style sauce, harissa, berry vinegar |
| September | Apple, pear, kohlrabi, beet, last of the cucumbers | Sauerkraut with apple and caraway, fermented beets, apple scrap vinegar, hard cider |
| October | Cabbage, cauliflower, daikon, turnip, fennel, apple, last of the chilies | Napa cabbage kimchi, kkakdugi, giardiniera, honey-fermented cranberries |
| November | Cabbage, Brussels sprouts, kohlrabi, celeriac, leek, apple, lemon | Homemade sauerkraut, white kimchi, honey-fermented cranberries, preserved lemons, hard cider |
| December | Cabbage, savoy cabbage, turnip, daikon, celeriac, lemon | Juniper and bay leaf sauerkraut, preserved lemons, apple cinnamon kombucha, spiced mead |
In the combiner, "What can I ferment with what I have?", the month's ingredients come up in a group of their own, and in the recipes you can filter by season.
What has no season
Carrots, onions, garlic, ginger and turmeric are around all year, and with them, brine-fermented carrots with ginger, fermented red onions or curtido. Kombucha, water and milk kefir, yogurt, sourdough, shio koji and miso have no month either: they depend on a culture or a dry grain, not on the harvest.
Long ferments suit the months when there's little produce. A miso started in winter spends months maturing; a sourdough starter can be made any week of the year.
The season is in your kitchen too
The month changes the temperature of your kitchen, and the temperature changes the ferment. These are the NCHFP's figures for sauerkraut, from the USDA-backed National Center for Home Food Preservation45:
| At home | What happens |
|---|---|
| Below 16 °C (60 °F) | May not ferment |
| 16–18 °C (60–65 °F) | 5 to 6 weeks |
| 18–21 °C (65–70 °F) | 3 to 6 weeks |
| 21–24 °C (70–75 °F) | 3 to 4 weeks |
| Above 24 °C (75 °F) | May turn soft |
Between 18 and 21 °C (65 and 70 °F) the NCHFP gives no times: Fervida uses the span of its two neighboring bands, and that is a house rule.
- In winter, an unheated kitchen can drop below 16 °C (60 °F). Find a warmer corner, away from windows and radiators, and expect it to take longer.
- In summer, the problem is heat. Find the coolest spot in the house and check your ferments often6. If even there you can't stay below 24 °C (75 °F), wait for cooler weather to start a sauerkraut.
The US, Spain and the south
The calendar is the same in both countries, but each region runs it earlier or later. In Florida, Southern California, southern Spain or the Canary Islands, summer starts sooner and lasts longer, and some winter vegetables grow nearly all year. In the northern US, cabbage is harvested at the end of summer: Washington State's extension service recommends cabbage harvested between mid-August and mid-September7.
In the Southern Hemisphere, from Argentina, Chile or Uruguay to Australia, add six months: what's in season here in January is in season there in July. And wherever you are, your local market knows more than any table.
Where every number comes from
Every number in the text leads to its figure: the exact sentence from the official guide it comes from, in its own language.
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1
Use fresh, in-season produce
“Use fresh, in-season produce.”
University of Minnesota Extension · Preserving food at home: Fermentation (reviewed 2026) · read on October 25, 2026
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2
Firm, fresh heads, 24 to 48 hours after harvest
“For the best sauerkraut, use firm heads of fresh cabbage. Shred cabbage and start kraut between 24 and 48 hours after harvest.”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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3
Start pickles within 24 hours of picking
“Pickling process should be started within 24 hours after gathering.”
Clemson Cooperative Extension, Home & Garden Information Center · Common Pickle Problems (HGIC 3101, revised August 2020) · read on October 26, 2026
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4
3 to 4 weeks at 70–75 °F; 5 to 6 at 60–65 °F
“At temperatures between 70º and 75ºF, kraut will be fully fermented in about 3 to 4 weeks; at 60º to 65ºF, fermentation may take 5 to 6 weeks.”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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5
Below 60 °F it may not ferment; above 75 °F it softens
“At temperatures lower than 60ºF, kraut may not ferment. Above 75ºF, kraut may become soft.”
National Center for Home Food Preservation (USDA, University of Georgia) · Sauerkraut · read on October 20, 2026
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6
In summer, find a cool spot and check your ferments often
“Look for a cool place in your home and when fermenting in the summer, plan to check your ferments often for doneness.”
K-State Research and Extension (Kansas State University) · Taking a New Look at Fermented Foods (MF3491, June 2020) · read on October 20, 2026
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7
In Washington, cabbage harvested from mid-August to mid-September is best
“preferably harvested between mid-August and mid-September”
Washington State University Extension, Lewis County · Sauerkraut Making · read on October 26, 2026