When to Plant Bok Choy
Planting Window
- Sow or transplant
- ~2 weeks before last frost
| USDA Zone | Typical Window |
|---|---|
| Zone 5 and colder | April (spring), plus August (fall) |
| Zone 6-7 | March-April, plus August |
| Zone 8 and south | Fall through early spring only |
Bok choy is a fast-maturing Asian brassica - typically 45-60 days - that shares the bolting sensitivity common across the brassica family, triggered by both heat and the long daylight hours of early summer, which pushes most of its growing window toward the cooler edges of the season rather than the middle.
Direct Sowing or Transplanting
Bok choy's relatively fast maturity - as little as 45 days for a full-size head - means a spring planting can usually be harvested and cleared before the riskiest bolting-inducing stretch of early summer even arrives, regardless of whether it started as a nursery transplant or direct-sown seed.
Baby vs. Full-Size Harvest
Bok choy can be harvested at a small "baby" stage after roughly 30 days for a tender, mild crop, or left to reach full size at the standard 45-60 day maturity window - some seed is specifically bred and marketed for baby harvest, with closer spacing intended from the start, rather than simply being the same variety picked early.
Shanghai Types Are More Compact and Faster
Shanghai-style bok choy, with pale green stems and a more compact, rounded shape, tends to mature slightly faster and stay smaller than standard white-stemmed bok choy - a practical consideration for tight succession planting, since the faster types spend less time in the ground at risk of bolting during a marginal weather stretch. Standard white-stemmed types also tolerate a slightly harder frost than the more tender Shanghai types, worth weighing for the earliest planting at the edge of the transplant window.
Succession Sowing Around the Bolt-Risk Window
A single bok choy sowing holds at peak quality for only a narrow window before bolting risk climbs, so spacing new short rows roughly two to three weeks apart through cool spring - then pausing entirely through summer's hottest stretch before resuming in late summer - keeps harvests coming without gambling everything on one planting.
Flea Beetles Are the Main Early Pest
Flea beetles are the most common early-season pest on bok choy, riddling young leaves with small round holes faster than the plant can outgrow the damage - floating row cover left on from sowing or transplanting until plants are more established is the most reliable non-chemical protection.
Zone boundaries follow the USDA Plant Hardiness Zone Map (2023 revision); frost windows reflect NOAA/NCEI climate normals. Both are typical historical ranges, reviewed annually - not a forecast or a guarantee for any single year. See Methodology & Sources.
Frequently Asked Questions
If a planting has already started to bolt, is it still worth eating, or should I just pull it?
It's worth a look before you pull it - the young flower stalks and buds that form as bok choy bolts are tender and edible, much like the flowering brassica stems some cooks grow on purpose. The leaves do turn more bitter once flowering starts, but stir-frying the flower shoots is a reasonable way to get something usable out of a planting that's already committed, rather than composting the whole thing.
Does harvesting at the baby stage lower the bolting risk compared to letting a planting reach full size?
It generally does, since a baby harvest at around 30 days spends noticeably less total time in the ground exposed to a marginal warm or long-day stretch than a planting left the full 45-60 days to size up. That shorter window is part of why a baby-harvest planting can often be pushed a bit later into a warming spring than a full-size planting would safely tolerate.
Are there bok choy varieties bred to resist bolting, so I could plant closer to summer than the general guidance suggests?
Some hybrid varieties are bred specifically for better bolt resistance, and seed catalogs usually flag that trait directly on the packet. Even so, treat it as buying an extra couple of weeks of safe planting window rather than a license to sow in the height of summer, since heat and day length pressure only intensifies as the season goes on.