How to make kimchi at home

TL;DR

A standard head of napa cabbage becomes kimchi through three moves: salt it heavily for 2 hours to draw out water, rinse and drain, then coat every leaf with a paste of gochugaru, garlic, ginger, fish sauce, and cooked glutinous rice porridge. Pack it tight into a jar with 2 inches of headspace, leave at room temperature for 1 to 3 days until it tastes tangy and faintly fizzy, then refrigerate.

Two things separate good homemade kimchi from mediocre homemade kimchi: using actual gochugaru (not generic chile flakes) and salting the cabbage enough in step one. Everything else is preference.

What kimchi actually is

Kimchi is a lacto-fermented vegetable dish, most commonly made from napa cabbage (baechu kimchi) coated in a seasoned paste. The lactic acid bacteria naturally present on the cabbage convert sugars into lactic acid, dropping the pH from around 6.5 down to roughly 3.5 to 4.0 over a few days. That pH drop preserves the cabbage, kills off spoilage organisms, and produces the characteristic sour tang.

The paste itself does not ferment the cabbage; the microbes on the cabbage do. The paste provides flavor, color, umami, and a small sugar boost to kickstart the bacteria. This is why the salt-and-drain step is the true engine of the recipe: it creates a low-water, high-salt environment where lactic acid bacteria thrive and their competitors do not.

There are dozens of regional and seasonal variants (kkakdugi with radish, oi sobagi with cucumber, baek kimchi without pepper, mul kimchi as a water kimchi). This guide covers baechu kimchi, the whole-cabbage version that most people mean when they say “kimchi.”

The conditions

Three variables to get right:

1. Salt concentration during the initial brine. You want the cabbage leaves to lose roughly 15 to 20% of their weight in water. Under-salted cabbage produces watery, limp kimchi. Over-salted cabbage never ferments properly because the salt inhibits even the beneficial bacteria. The target after rinsing is a leaf that bends without snapping and tastes distinctly salty but not aggressively so.
2. Fermentation temperature. 65 to 72°F is ideal. Warmer means faster and more aggressive fermentation with a shorter window between “perfect” and “too sour.” Colder means slower fermentation and a longer window, but risks not fermenting enough before you refrigerate.
3. Time at room temperature. 1 to 3 days for most kitchens. This is the active fermentation phase where most of the lactic acid is produced. After that, refrigeration slows fermentation to a crawl but does not stop it; kimchi keeps developing in the fridge for weeks.

The same principles apply to sauerkraut, which shares the lacto-fermentation mechanism but uses a dry salting approach with shredded cabbage rather than a paste on quartered leaves, and to lacto-fermented pickles, where whole cucumbers sit in a poured salt brine.

Step by step

1. Quarter and salt the cabbage

Cut the cabbage lengthwise into quarters, keeping the core intact so the leaves stay attached. Working over a large bowl, sprinkle coarse salt between every layer of leaves, using more at the thick base of each leaf and less at the tips. For a 2 to 2.5 lb cabbage, you want about 1/3 cup of coarse salt total.

Place the salted quarters cut-side up in the bowl. Pour a few cups of water into the bowl until the cabbage is partially submerged. Let sit for 2 hours, flipping the quarters every 30 minutes so the salt distributes evenly. By the end, the leaves should be visibly wilted and a leaf tip should bend 180 degrees without breaking.

Failure mode: if the leaves still snap crisply after 2 hours, salt more and wait another hour. Under-salting here cannot be fixed later.

2. Rinse and drain thoroughly

Rinse the cabbage under cold water three times to remove excess salt. Squeeze each quarter gently, then set them cut-side down in a colander to drain for at least 30 minutes. You want the cabbage as dry as practical before adding the paste.

Taste a small piece of the thick base of a leaf. It should taste pleasantly salty, similar to a well-seasoned pickle. If it tastes aggressively salty, rinse once more. If it tastes bland, sprinkle a teaspoon of salt into the paste.

3. Make the rice porridge

Whisk 2 tablespoons of glutinous rice flour into 1 cup of cold water in a small saucepan. Bring to a simmer over medium heat, whisking constantly, until it thickens into a translucent gel, about 3 to 5 minutes. Stir in 1 tablespoon of sugar off the heat and let it cool completely.

The porridge does two jobs: it binds the gochugaru paste to the cabbage so it does not slide off, and it provides an initial food source for the lactic acid bacteria. Skipping the porridge produces thinner kimchi with less clingy paste. It is not strictly required, but it is the difference between kimchi that looks and tastes right and kimchi that looks slightly wrong.

4. Blend the paste

In a food processor or blender, combine:

• 6 to 8 cloves of garlic
• A 2-inch knob of peeled ginger
• Half a Korean pear or a small apple, cored
• 3 tablespoons fish sauce (or the soy-and-miso substitute)
• 1 tablespoon salted shrimp, optional but recommended for depth
• The cooled rice porridge

Blend into a smooth paste. Transfer to a large bowl and stir in 1/2 to 3/4 cup of gochugaru. Start with 1/2 cup for a mild kimchi and go up from there. Let the paste sit for 10 minutes so the gochugaru hydrates and blooms into a deep red.

Add the vegetables:

• 1/2 daikon radish, cut into matchsticks
• 4 to 5 scallions, cut into 2-inch lengths
• Optional: a handful of Asian chives (buchu) cut to the same length

Stir everything together into a thick, deep-red slurry.

5. Coat every leaf

Put on gloves. Take one quarter of drained cabbage, lay it in the bowl of paste, and work the paste between every single leaf, from the thick base to the tip. Do not just smear it on the outside; separating and coating each leaf is the point of quartering rather than shredding.

Once every leaf is coated, fold the quarter in half so the outer leaves wrap around it, then place it in the jar. Repeat with the remaining quarters, packing them down as you go to eliminate air pockets. Pour any remaining paste and juices from the bowl over the top.

Leave at least 2 inches of headspace. Kimchi expands and bubbles aggressively for the first few days; a full jar will push brine out of the lid and onto your counter.

6. Ferment and taste

Close the jar loosely, or use a fermentation lid if you have one. Set the jar on a plate to catch any overflow. Leave at room temperature (65 to 72°F).

Starting at 24 hours, open the jar and taste a small piece from the top:

• Still tastes like salty raw cabbage with a paste on it. Not ready. Give it another 12 to 24 hours.
• Tangy, mildly sour, small bubbles rising when you press down. Ready. Refrigerate.
• Distinctly sour, actively fizzing, brine has risen and darkened. Slightly past the fresh-kimchi window but still good; refrigerate immediately.
• Aggressively sour, smells sharp and vinegary. Overfermented for fresh eating; use in kimchi jjigae, fried rice, or pancakes.

Most batches at 68 to 72°F are ready between 36 and 60 hours. Colder kitchens can take 3 or 4 days.

What you might see along the way

Brine rising and overflowing the jar. Normal, especially in the first 2 days. This is CO2 pushing brine up through the paste. Burp the lid once a day and keep the plate underneath.

Bubbles forming inside when you press the cabbage. Active fermentation. Expected and good.

A slightly funky smell that gets sharper over time. Normal. Fresh kimchi smells savory-funky-garlicky. Ripe kimchi smells sour-funky-garlicky. Rotten smells (sulfurous, putrid) are not.

A thin white film on the surface. Probably kahm yeast, not mold. Skim it off and push the cabbage back under the brine. See kahm yeast versus mold for the full identification tree.

Fuzzy or colored growth on the surface. Mold. Discard the batch. This is rare in properly-salted kimchi because the salt and quick acidification block mold, but it can happen if the cabbage was not fully submerged in its own brine.

Common mistakes

Using the wrong pepper. Generic chile flakes, cayenne, and even Aleppo pepper are not substitutes for gochugaru. Gochugaru is coarser, sweeter, fruitier, and less aggressively hot than most Western chile flakes. Using cayenne produces kimchi that is punishingly spicy without any of the fruit-forward character. Buy actual gochugaru; a 1 lb bag lasts through many batches and keeps for a year in the freezer.

Under-salting the initial cabbage. The salt-and-drain step is where kimchi gets its texture. Skip it or shortcut it and you get watery, limp kimchi that never crisps up. The visual test is the leaf tip bending 180 degrees without snapping; if it snaps, salt more.

Iodized table salt. Iodine inhibits lactic acid bacteria. Kimchi made with iodized salt ferments slowly, unevenly, and can develop bitter off-flavors. Use non-iodized coarse sea salt, kosher salt, or Korean cheonilyeom.

Sealing the jar tight. Kimchi produces CO2 fast and aggressively. A tightly sealed jar can crack, pop its lid, or spray brine across the kitchen. Leave the lid loose, or use an airlock fermentation lid, or burp the jar daily.

Rushing to the fridge. Refrigerating after 12 hours produces kimchi that is barely fermented, tastes mostly like salted cabbage with paste, and never develops proper depth. Wait for the tang to actually arrive at room temperature; the fridge is for slowing an already-fermenting product, not for finishing an unfermented one.

Cutting the cabbage too small. Shredded kimchi (mak kimchi) is a legitimate variant, but quartered whole-leaf kimchi holds the paste better between leaves and produces a more traditional texture. If you shred, expect the paste to pool at the bottom of the jar rather than staying with the cabbage.

Troubleshooting

My kimchi tastes bitter, not sour. Usually iodized salt or old gochugaru. Iodized salt inhibits fermentation and lets off-flavor microbes dominate. Old gochugaru turns dull, brown, and bitter rather than fruity-sweet. Check both. If your gochugaru is more brown than red, replace it.

The paste slid off the cabbage and pooled at the bottom. Either you skipped the rice porridge, or the cabbage was still wet when you applied the paste, or you shredded rather than quartered. The porridge is what makes the paste cling. Next batch, use the porridge and drain the cabbage longer.

My kimchi is sour but has no fizz or effervescence. Fine, especially in a cold kitchen. Fizz is a sign of active fermentation; a properly acidified kimchi that has been refrigerated will not fizz much. Sourness is the more important indicator that lactic acid has been produced.

It tastes too salty even after a week. You over-salted in step one and did not rinse enough. Salvage by mixing in unsalted grated daikon radish, which will absorb salt and dilute the kimchi. Next batch, use less salt or rinse three times instead of two.

The kimchi went straight from “not ready” to “overfermented” in a day. The kitchen was too warm. Above 75°F, the window between perfect and overdone can be under 12 hours. Ferment in a cooler spot (basement, garage in mild weather, top of the fridge in a cold kitchen) or start checking every 6 hours after the 24-hour mark.

Small holes or hollowing in the thick leaf bases. Gas pockets from CO2 production, usually harmless and indicates strong fermentation. If accompanied by off-smells or slime, it is a different problem; discard.

White stuff on the surface, but the kimchi smells fine. Almost certainly kahm yeast. Skim, push everything under the brine, add a small weight if you have one, and continue. If the “white stuff” is fuzzy or has any color to it, that is mold, and the batch is done.