Bok choy (Brassica rapa subsp. chinensis), also spelled pak choi, is one of the quickest and most satisfying vegetables a home gardener can grow — a crisp, mild Asian cabbage with thick white or green stalks and tender dark leaves that goes from seed to harvest in as little as 45 days, and baby heads even faster. The secret to success is treating it as a cool-season crop: bok choy thrives in the mild temperatures of spring and fall but bolts straight to flower in summer heat or after a cold snap. Time it right, keep it watered, and stay ahead of flea beetles, and you’ll be cutting tender heads for stir-fries in barely six weeks. This guide covers the full cycle from sowing to harvest.
In this guide
Key Takeaways
- Bok choy is a fast cool-season crop — best in spring and fall, with heads ready in 45–60 days.
- Sow ¼–½ inch deep; thin baby types to 6 inches and full-size types to 8–12 inches apart.
- Give it full sun to part shade and rich, moist, well-drained soil at pH 6.0–7.5.
- Heat, cold snaps, and dry stress all cause bolting — keep moisture and temperatures even.
- Flea beetles are the number-one pest; floating row cover from sowing is the best defense.
Choosing a Variety
Bok choy comes in full-size and baby (mini) forms, and in white-stemmed and green-stemmed types. ‘Joi Choi’ is a vigorous, bolt-resistant white-stemmed standard. ‘Toy Choy’ and ‘Mei Qing Choi’ are quick baby types ideal for tight spacing and container growing. ‘Win-Win Choi’ is heat- and bolt-tolerant for pushing the season. For spring sowing especially, choose a variety described as slow-bolting, since spring crops are the most prone to running to seed. Baby types are the most beginner-friendly because they mature so fast there’s less time for anything to go wrong.
When to Plant Bok Choy
Bok choy grows best at temperatures between 55°F and 70°F. There are two prime planting windows. For a spring crop, sow as soon as the soil can be worked, two to three weeks before your last frost, and aim to harvest before summer heat arrives — fast baby types are best here since full-size heads may bolt as days lengthen and warm. For a fall crop — often the better one — sow in late summer, roughly six to eight weeks before your first fall frost, so plants mature into cooling weather; cool fall nights actually sweeten the leaves, and mature plants tolerate light frost.
Avoid sowing in the heat of midsummer, when high temperatures and long days almost guarantee bolting. In mild-winter climates (zones 9–10) bok choy can be grown straight through the cool season. Succession-sow small batches every two to three weeks within the cool windows for a continuous supply.
Light, Soil and Sowing
Give bok choy full sun in spring and fall; in warmer spells, light afternoon shade helps slow bolting. It’s a fast, leafy brassica that demands fertile, moisture-retentive but well-drained soil rich in organic matter, with a pH between 6.0 and 7.5. Work two to three inches of compost into the bed before planting, plus a balanced fertilizer, since rapid leafy growth needs steady nutrients.
You can direct-sow or transplant, but bok choy — like many brassicas — can bolt if its roots are disturbed or stressed during transplanting, so direct sowing is often the safer route. Sow seeds ¼ to ½ inch deep, and once seedlings have a couple of true leaves, thin baby types to about 6 inches apart and full-size types to 8 to 12 inches apart, with rows 12 to 18 inches apart. Crowded plants compete and are more bolt-prone. Bok choy’s shallow roots and compact size make it an excellent container and raised-bed crop for small spaces.
Watering and Feeding
Consistent moisture is the single most important factor with bok choy. It’s a shallow-rooted, fast-growing leafy crop that needs about one to one-and-a-half inches of water a week, and it will not forgive drying out — dry stress turns the stalks fibrous, the flavor bitter, and frequently triggers bolting. Water evenly and deeply, mulch to conserve moisture and keep the soil cool, and never let it wilt. Containers in particular may need daily watering.
Because it grows so quickly, bok choy benefits from a steady supply of nitrogen. Mix a balanced or nitrogen-leaning fertilizer into the soil at planting, then side-dress with compost or a dilute liquid feed two to three weeks after thinning to fuel leafy growth. Don’t overdo nitrogen right before harvest, but generally, well-fed bok choy grows fast and tender — and speed is your friend, since the faster it matures the less time pests and bolting have to interfere.
Preventing Bolting
Bolting — premature flowering — is the most common frustration with bok choy, and it has three main triggers: heat (sustained temperatures above about 75–80°F), exposure of young plants to a cold snap below ~50°F for several days (which can vernalize them into thinking winter has passed), and any check to growth from drought or root disturbance. Manage all three by planting in the right cool window, choosing slow-bolting or baby varieties, keeping moisture and feeding steady, using row cover to buffer temperature swings, and harvesting promptly once heads are ready. Once a plant starts sending up a flower stalk, harvest it right away before the leaves turn bitter.
Pests and Diseases
As a brassica, bok choy attracts the usual cabbage-family pests. Flea beetles are the worst offenders, riddling young leaves with tiny shotgun holes; cover seedlings with floating row cover from the day you sow, and keep the bed weed-free. Cabbage worms and loopers (green caterpillars) chew larger holes — handpick them or use a Bacillus thuringiensis (Bt) spray. Aphids, slugs and cabbage root maggots can also appear; row cover, slug traps and good garden hygiene keep them in check.
Diseases include downy mildew and other fungal leaf spots in wet, crowded conditions, and clubroot, a soil-borne disease that deforms brassica roots. Prevent fungal trouble with good spacing, airflow and base watering, and prevent clubroot by rotating brassicas so bok choy doesn’t follow cabbage, broccoli or other crucifers in the same bed for at least two to three years.
Harvesting Bok Choy
Bok choy is flexible about when you pick it. Baby types are ready in about 30 to 45 days and full-size heads in 45 to 60 days. You can harvest in three ways: snip individual outer leaves as you need them, leaving the center to keep growing for a cut-and-come-again supply; cut the entire head off about an inch above the soil with a sharp knife, after which the stub may resprout for a small second harvest; or pull the whole plant, roots and all. Harvest in the morning when the plants are crisp and fully hydrated.
Don’t wait too long — bok choy left in the ground past maturity, especially as weather warms, will bolt and turn bitter. If you see a flower stalk forming or a head beginning to loosen, harvest immediately. In fall, a light frost improves the flavor, but harvest before a hard freeze damages the tissue.
Storing Bok Choy
Store unwashed heads in a perforated plastic bag in the crisper drawer, where they keep crisp for up to a week. Wash just before using. Bok choy doesn’t dry or freeze raw well because of its high water content, though blanched and frozen leaves work for soups and stir-fries. For the best texture and flavor, treat it as a fresh, fast-turnover crop and grow it in succession so you always have a young head ready. If you enjoy quick-growing edibles like this, our guide to regrowing green onions from scraps pairs perfectly with a bok choy stir-fry garden.
Frequently Asked Questions
How long does bok choy take to grow?
Baby (mini) types are ready in about 30–45 days, and full-size heads in 45–60 days. That speed is part of its appeal — succession-sow every few weeks during cool spring and fall windows for a steady supply.
Why does my bok choy keep bolting?
Bolting is triggered by summer heat, by a cold snap chilling young plants, and by drought or transplant stress. Plant in the cool windows of spring and fall, keep moisture steady, choose slow-bolting varieties, and harvest promptly.
Can I harvest bok choy more than once?
Yes. Snip outer leaves as a cut-and-come-again crop while the center keeps growing, or cut the whole head an inch above the soil and the stub will often resprout a small second harvest.
What’s eating holes in my bok choy leaves?
Tiny shotgun-pattern holes are flea beetles; larger ragged holes are cabbage worms or loopers. Cover plants with floating row cover from sowing, handpick caterpillars or use Bt, and keep the bed weed-free.
Can bok choy grow in containers?
Yes — it’s ideal for pots and raised beds thanks to its shallow roots and compact size. Use a container at least 6–8 inches deep, rich moist potting mix, and choose a baby variety like ‘Toy Choy’ for fastest results.