Bok choy, also called pak choi, is a fast-growing Asian green with crisp white or green stems and tender leaves. Baby bok choy can be ready in about a month. It is a cool-season member of the cabbage family that bolts quickly in heat, long days or a cold snap, so timing matters. This page covers when to sow, how to space it, how to care for it and how to harvest it.
Bok choy at a glance
| Type | Vegetable |
|---|---|
| Season | Cool-season |
| Sun | Full sun to part shade |
| Plant spacing | 12 in |
| Row spacing | 18 in |
| Per square foot | 1 |
| Seed depth | ½ in |
| Days to maturity | 45–60 from seed |
| How to start | Direct sow or transplant from 4 weeks before last frost; again in late summer |
| Water | 1 in per week |
These are the same numbers our plant spacing, square foot and harvest date calculators use. See every crop in the plant database.
When to plant bok choy
Sow bok choy directly or set out transplants from about 4 weeks before your last spring frost, once the soil can be worked. Young plants exposed to a week or more of cold below about 50°F may bolt, so protect early plantings with row cover. Fall is often the best season: sow in late summer, about 6 to 8 weeks before your first fall frost.
Check your dates with the frost dates by ZIP code tool. Small sowings every 2 to 3 weeks in spring and fall give a steady supply.
How to plant bok choy
- Choose sun or part shade. Full sun in cool weather; afternoon shade as days warm.
- Sow 1/2 inch deep. Sow seeds a couple of inches apart and thin to the spacing in the table above, or closer for baby bok choy. Eat the thinnings.
- Use rich, moist soil. Mix compost into the bed before sowing so plants grow quickly.
- Rotate. Avoid spots where cabbage-family crops grew recently. The crop rotation checker helps.
Caring for bok choy
Keep the soil evenly moist, about an inch of water a week; dry soil makes bok choy bolt. Mulch helps keep roots cool. The garden watering calculator turns this into gallons.
A side-dressing of a nitrogen-rich fertilizer a few weeks after sowing keeps plants growing fast and tender. Cover plants with row cover from sowing to keep flea beetles and cabbage worms off and to protect them from cold snaps.
Companion plants
| Grow nearby | Onions, garlic, lettuce, carrots, beets, dill, celery |
|---|---|
| Keep apart | Strawberries; other cabbage-family crops in the same spot as last year |
Onions and garlic help confuse cabbage pests, and dill attracts beneficial insects. Lettuce, carrots and beets share bed space easily. Check other pairings with the companion plant finder.
Common problems
| Problem | What you see | What to do |
|---|---|---|
| Bolting | A flower stalk shoots up before the plant reaches full size | Caused by heat, long days, dry soil or a long cold snap. Sow in spring and fall, protect from cold, keep watered and harvest young. |
| Flea beetles | Many tiny holes in leaves | Use row cover from sowing. See the pest identifier. |
| Cabbage worms | Green caterpillars and ragged holes in leaves | Use row cover, hand-pick caterpillars or spray Bt. |
| Slugs and snails | Ragged holes, especially in stems and inner leaves | Hand-pick at dusk or use iron phosphate bait. |
| Aphids | Small insects clustered in the heart | Spray off with water and rinse well before eating. |
Not sure what you are looking at? The plant problem identifier ranks likely causes from the symptoms you see.
When and how to harvest
Harvest baby bok choy when plants are about 6 inches tall, around 30 days after sowing, and full-size plants when they reach 10 to 15 inches. Cut the whole plant at the base, just above the soil; a stump left in the ground often sprouts a few more small leaves. You can also pick outer leaves a few at a time.
Harvest right away if you see a flower stalk forming. Store unwashed bok choy in a bag in the fridge and use within a few days. Use the harvest date calculator to see when yours will be ready.
Plan your bok choy
- Plant spacing calculator: how many plants fit your bed
- Planting calendar: sowing and transplant dates for your frost dates
- Frost dates by ZIP code: your last spring and first fall frost
- Harvest date calculator: when your crop will be ready
Frequently asked questions
How far apart should I plant bok choy?
Space bok choy 12 inches apart in rows 18 inches apart. In a square foot garden, plant 1 per square foot.
How deep do I plant bok choy seeds?
Sow seeds ½ inch deep.
How long does bok choy take to grow?
Most varieties are ready 45–60 days from seed. Check the seed packet, because early and late varieties differ.
How much water does bok choy need?
About 1 inch of water a week, from rain and watering combined. Keep the soil evenly moist; dry soil makes bok choy bolt.
Why does my bok choy bolt so fast?
Bok choy bolts in heat, long days, dry soil or after a week or more below about 50 degrees F. Grow it in spring and fall, protect young plants from cold and keep it watered.
When is bok choy ready to harvest?
Baby bok choy is ready at about 6 inches tall, around a month after sowing. Full-size plants are ready at 10 to 15 inches.