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Why Is My Chinese Cabbage Flowering

Chinese cabbage comes in two types: Napa cabbage (an oblong, pale green head) and bok choy (leafy stalks radiating from a bulb). Both have a milder taste than green cabbage and are easy to grow in your garden. In the summer, you may find a plant with a flower stalk growing out of it when you go out to harvest some for your dinner. Why is my Chinese cabbage flowering?

A Chinese cabbage that’s flowering is bolting. This is usually caused by warm summer weather. Chinese cabbage is a cool weather plant that needs to be planted early in the spring to mature before the temperature gets too warm.

Because of this, some people prefer to plant it for a fall harvest instead. However, flowering can also be caused by cold weather or lack of water or nutrients.

Now that you know why your Chinese cabbage is flowering, you may have other questions. Let’s dive in to learn more about bolting, how it affects the plant and the cabbage, and ways you can delay it.

What Is Bolting?

Bolting, also known as ‘going to seed,’ is when a vegetable plant suddenly sends up a flower stalk. This signals the end of the growing season for the plant, which now puts all its energy into producing flowers rather than growing more tasty leaves.

Seeds will form from the flowers so the plant can reproduce. A vegetable plant’s purpose is to reproduce by making seeds. The gardener’s purpose for planting vegetables is to harvest and eat them.

So, the trick is to harvest your Chinese cabbage before it bolts and starts the seed-making process.

Harvest Napa cabbage, not by size, but when the head feels firm and dense. Unlike round green cabbage, Napa won’t stand when mature, so pick it up as soon as it’s ready.

Harvest bok choy either by waiting for the whole head to mature while the oldest leaves are still tender or by cutting a few leaves at a time, starting with the oldest, largest leaves on the outside of the plant.

When a plant bolts, it’s too late to do anything about it. You can cut the flower stem off, but the cabbage plant won’t start growing leaves again. The cabbage’s stalk will produce flowers, then seeds, and die.

What Causes Bolting?

Bolting is caused when a plant reaches the end of its life cycle or experiences stress and doesn’t have enough energy to keep growing.

Chinese cabbage is a cool-weather crop. When planted in the spring, it’s vulnerable to bolting in the summer, especially the Napa type. Other varieties of cabbage are also sensitive to warm temperatures, but Chinese cabbage is even more so. It doesn’t do well with too much heat or sunlight.

Other causes of bolting with Chinese cabbages are low temperatures, inadequate water, or nutrient stress.

If young plants are exposed to low temperatures, they can bolt. For Napa cabbage, this is below 45 degrees F, and for bok choy, this is below 50 degrees F.

Insufficient water or nutrients causes stress for the plants. This causes them to stop growing leaves and put what energy they have into making seeds.

Should You Let Chinese Cabbage Flower?

When a flower stalk grows out of a Chinese cabbage plant, the growth of the cabbage stops. The leaves will become bitter and tough quickly.

If you see a flower stalk on your Chinese cabbage, you should immediately pick the cabbage before it gets too bitter-tasting.

Even if you cut off the flower stalk and the plant grows more leaves, they will be small, tough, and taste unpleasant. The cabbage’s time for producing a flavorful vegetable is over.

If you want to collect seeds for your next crop, you can leave the flowers alone and harvest the seeds when they’re dry. Or enjoy the yellow flowers and let them attract bees to your garden.

How Do You Keep Chinese Cabbage from Bolting?

Bolting is natural for leafy vegetables such as Chinese cabbage, so it will happen eventually. A gardener wants to delay it until the Napa cabbage head is mature enough to harvest or harvest as many bok choy leaves as possible.

Ways to do this:

  • For spring planting, start seeds indoors so you can transplant them outside as soon as possible after the last frost.
  • Place the spring plants to get partial shade, especially in the afternoon. You can also use a shade cloth.
  • Use a row cover to shield plants from the hot sun and low nighttime temperatures.
  • Plant in mid to late summer or early fall to avoid the summer heat when the cabbages are maturing. In this case, the plants should get full sun.
  • Water regularly and add compost to the soil.
  • Use mulch around the plants to retain moisture and keep the soil temperature constant.
  • Make sure the cabbage plants get enough phosphorous and calcium.
  • Find a bolt-resistant variety to plant, such as Emiko, Fun Jen, Hon Tsai Tai, Jade Pagoda, Maruba Santoh, and Shuko.
  • Try Michihili and loose-leaf Chinese cabbages, such as Jade Pagoda.
  • Plant Chinese cabbage that matures early, such as Soloist, a baby Chinese cabbage that can be harvested in 40-50 days rather than 60-80 days.
  • Plant every two weeks to have a better chance of harvesting over the growing season in the event of unpredictable weather.

These methods can help you have the longest growing season possible to benefit from the fruits of your labor.

Final Thoughts

Gardening involves giving your vegetables the growing conditions they need so that you have the maximum harvest. By learning what Chinese cabbages need to thrive, you can delay the bolting process and have a larger crop.

Chinese cabbage grows best in planting zones 4-9, depending on the variety. Learning the right time to plant Chinese cabbage in your area can be tricky to avoid too warm and too cold temperatures. Adding these delicious vegetables to your menu will be worth the effort.

Napa is sweeter and milder-tasting than green cabbage, and bok choy has a taste between green cabbage and chard. Both can be eaten raw in a salad, cooked in a stir-fry, or added to a soup.