Here's Your Timeline for Growing Napa Cabbage

Napa cabbage is one of my favorite greens to grow in the garden. I never had a ton of success with other types of cabbages. They'd never form a full cabbage head. Or if they did form a head, they'd bolt before I could harvest them. Or I'd harvest them and discover the insides were full of gross critters I don't want to eat.

But Napa cabbage has always been a winner for me. It's fast-growing, and I've had a lot of success with this variety. Plus, it's so delicious, from those outer leaves that make a quick salad to the full heads that produce the most delicious stir fries ever.

If you want to grow your own Napa cabbage, you've got to start it early. You can't wait until spring has sprung to start this plant by seed. You need close to 120 days to get these plants from seed to harvest. I'll help you figure out when to start Napa cabbage seeds indoors this winter and how to grow this gorgeous veggie in your kitchen garden.

Here's your timeline for growing Napa cabbage at home.

Starting Napa Cabbage Seeds Indoors

Start Napa cabbage seeds indoors during the winter for best results. Even if your last frost date is far, far away, you should be starting large cool season plants like cabbage, kale, and broccoli.

A good general guideline is the early part of January, but if you want to figure out your specific date, look up your last anticipated frost date in the spring so you can count backwards to determine your exact indoor planting date. (Click here to find your last frost date in the US.)

You'll start your seeds for Napa cabbage and your other large cool season plants about 100 days before your last frost date. When I lived in Chicago, my cabbage seed sowing date was February. If you live in a warmer climate like Houston, your date is actually in December. If you're reading this in January, don't worry. We can all start our Napa cabbage seeds indoors right now. You'll just plant them outside a little sooner or later based on your climate.

Tips to Start Napa Cabbage Seeds Indoors

Gather your seed starting supplies, and then follow these simple steps to start your Napa cabbages by seed ahead of your growing season:

• Place just one Napa cabbage seed per cell, if you can make that happen.
• Keep the seed starting mix really nice and moist. You don't need a heating mat or anything because cabbages like the cool weather.
• As soon as you see your first green sprouts appear, put your tray under grow lights. Position the lights really low, just a few inches above those greens, so that you don't end up with leggy seedlings. (Leggy means your little stems are all stretched out and too thin.) We want nice, thick cabbages, and keeping the lights close but not to the point of burning the leaves is how you start robust, bushy seedlings.
• If you accidentally dropped more than one seed into a cell, go ahead and thin out the seedlings now so that there's just one cabbage seedling growing in each cell.

Every single day, you'll see your little greens getting bigger and bigger and bigger. Once your seedlings have grown four or five leaves, it's time to give them a larger growing space. Ideally, your soil will now be workable so you'll be able to transplant the seedlings to your garden space soon. If your seedlings have taken off but the weather's not right for moving them outside yet, you might need to pot them up to a 4-inch pot. I don't like to have to transition plants twice, but sometimes it's necessary to make sure the roots have room to grow.

Transplanting Napa Cabbage Seedlings

You're now nearing the time to move your Napa cabbage seedlings outdoors. You'll know the moment is coming when your soil loosens up a bit, the temperature rises, and the snow begins to melt. In Chicago, this is right around February. For me in Nashville, this is around the end of January.

As soon as the temperature warms up a bit, begin bringing your cabbage seedlings outdoors for a couple hours, just during the day, to harden them off. Don't put them in full sun and definitely don't expose to them really cold weather—temps in the 40s are ideal. Let your cabbages get used to the great outdoors for 4 to 5 hours, and then bring them back inside. Do this for a week or two as you near your planting date.

When you're about 75 days or so before your last frost date, it's time to transplant your cabbage seedlings to the garden. I planted my cabbage seedlings in the garden at the very beginning of March in Chicago. Now that I'm in Nashville, I plant them at the very beginning of February. As soon as the soil is workable and the temps are staying in the 40s and 50s, you're good.

Dig a little hole that's as deep as your seed starting tray and twice as wide as each cabbage root ball. Give each Napa cabbage a little bit less than one square foot. I like to grow mine in rows, so that I can squeeze in a ton of Napa cabbages by planting in windows.

Tending Napa Cabbage Seedlings

Your cabbage seedlings are frost tolerant, even frost resistant, so it's not a huge deal if you do have frost coming your way, which you likely will since you're still two months away from your last frost date.

You can put frost cloth and/or plastic sheeting over your cabbages on nights when the temps are expected to drop below freezing. You could even build a cold frame around them. My cabbage seedlings got frost and some snow on them all the time when I lived in Chicago. As soon as the weather cleared, the plants would be a little bit damaged but not too bad. They kept on growing right through the cold weather.

You should see a few new leaves emerging from the heart of the plant every few weeks. And then, as you get closer and closer to that last frost date, they're really going to take off. You might see a small head beginning to form as early as 50 days before your last frost date.

If any of those outside leaves look stressed or damaged, simply prune those leaves, leaving the interior of the plant to continue growing.

Once your plants are really growing, you can begin harvesting some of those outer leaves for stir fries, crisp salads, and sauerkraut. Again, make sure to leave the heart of the plant so it can keep producing.

Harvesting Your Napa Cabbage Plants

The 10 to 25 days after your last frost are your prime cabbage time. You're now officially the Napa cabbage lady, okay? You'll be harvesting a couple heads every week, depending, of course, on how many plants you put into the garden.

But here's the thing: You don't wanna miss this window. (Speaking as someone who has missed this window.) Once the temps climb into the 70s and 80s, your Napa cabbage plants are going to start bolting, or going to seed. That's when the taste of the leaves changes and the slugs start appearing. It's really sad to see all your hard work go to waste.

So you are on the clock. Put it in your calendar that you're going to harvest and enjoy your Napa cabbage plants every single week as soon as your last frost date has passed until they're all removed from the garden space.

Harvest your Napa cabbage heads by using a sharp knife or a hori hori to cut them right at the base. Plant new warm season plants around them. Your cabbage growing season comes to an end as soon as you transition fully into the warm season.

Growing a Second Round of Napa Cabbages

Here's the good news: If you loved your Napa cabbage, then you get to do it all again!

Start planning for your second round in the middle of your warm or hot season. Start Napa cabbage by seed indoors about 90 days before your first frost of the fall. Do the whole process over again, except this time, instead of planting your Napa cabbage and fearing the frost, you're going to be dealing with the heat. You might need to hide your cabbages in the shade of taller plants or use shade cloth so that they don't prematurely bolt. Once the temps drop down to the 60s, you're good.

Your cabbage plants will make it through the first frost, and then you're going to start to harvest those cabbage heads over the next 20 to 30 days after that first frost.

Time to Start Some Napa Cabbage Seeds!

And boom!, you just had two incredible seasons of Napa cabbage. You'll have to tell me if this isn't the best Napa cabbage you've ever had in your life.

Seriously, if you are looking for a way to up your game in the garden, to add something that's beautiful and so productive, then you've got to try my Napa cabbage plan. Make sure to keep this timeline in mind because these plants really do need like 120 days to go from seed to harvest.

Thanks for being here and making the garden ordinary again!

This post was adapted from S2 E4 of the Grow Your Self Podcast. Listen on Apple Podcasts and Spotify. Subscribe so you never miss a planting tip or vegetable tidbit!