How do you make sauerkraut and lacto-fermented vegetables from your garden?

Lacto-fermentation is the ancient technique that produces sauerkraut, kimchi, pickled cucumbers, and fermented hot sauce — all using nothing more than vegetables, salt, and time. No vinegar is added, no heat treatment is applied, and no starter culture is needed. The lactic acid bacteria already living on fresh vegetables do all the work, and the result is a preserved food with a deep, tangy complexity that no vinegar pickle can replicate.

For the home grower, lacto-fermentation is an ideal destination for cabbage, cucumbers, peppers, green beans, radishes, and mixed garden vegetables. These ferments keep for months in the fridge after the initial fermentation period and improve in flavour over time.

The dry-salt method for sauerkraut and shredded ferments

The dry-salt method is used for vegetables that release significant juice when massaged — primarily cabbage, but also carrot, fennel, and radish. Shred or grate the vegetable finely and weigh it. Add 2% of its weight in non-iodised salt — 20g per kilogram. Massage the salt into the vegetable for three to five minutes until a significant amount of liquid has been released. The vegetable should look wet and limp, and there should be a pool of brine at the bottom of the bowl. This natural juice is your brine — it needs to cover the vegetables entirely in the jar.

The brine-submersion method for whole or chunked vegetables

Cucumbers, whole green beans, carrot sticks, and other vegetables that don't release enough juice when salted use a different approach: a prepared brine. Dissolve 20g of non-iodised salt per litre of non-chlorinated water — use filtered or boiled-and-cooled water if your tap water is heavily chlorinated, as chlorine inhibits fermentation. Pack the vegetables tightly into sterilised glass jars with any flavourings — dill, garlic, peppercorns, chilli — then pour the brine over to cover completely. Leave at least 2.5cm of headspace at the top of the jar because the brine will bubble and expand during active fermentation.

Keeping vegetables submerged

The single most important rule in lacto-fermentation is that all vegetable matter must stay below the brine surface at all times. Anything exposed to air can develop mould. Use a small zip-lock bag filled with brine as a weight, a clean stone, or a purpose-made ceramic fermentation weight. Check daily for the first few days when fermentation is most active and push down any pieces that rise above the brine.

Fermentation timeline and when to refrigerate

Fermentation is fastest in warm conditions and slowest when cool. At 20–22°C, most lacto-ferments reach a pleasant sourness in three to five days. At 18°C, expect five to seven days; below 15°C, fermentation slows considerably and may take two weeks or more. Taste daily from day three — you are looking for a pleasantly sour flavour you enjoy eating. There is no single correct end point; sourness continues to develop the longer you leave it. Once it tastes right, seal the jar and refrigerate. Cold temperatures halt the active fermentation and preserve the current flavour profile.

Flavour additions for lacto-fermented vegetables

Plain salt ferments are delicious, but traditional additions deepen the flavour significantly. Caraway seeds and juniper berries in sauerkraut, dill and garlic in cucumber pickles, fresh ginger and garlic in a mixed vegetable kimchi-style ferment, or dried chilli in a hot fermented pepper sauce. Add flavourings with the vegetables at the start — they ferment alongside the vegetables and become incorporated into the final flavour.