Last Updated on September 17, 2026
How Many Bok Choy Plants per Square Foot?
4 bok choy plants per square foot, 6 inches apart, is the spacing the Plan My Garden planner uses, and it matches NC State Extension’s Plant Toolbox, which spaces or thins the crop to 6 inches apart. Grow it for a baby harvest instead and my square foot gardening chart packs it tighter, 9 per square, 4 inches apart. Let a head reach full size and University of Minnesota Extension widens that to 12 to 18 inches apart, which is 1 per square, or a checkerboard of every other square for the widest heads.
The spacing pattern
| Per square foot | 4 plants, on a 2 by 2 grid |
|---|---|
| Inches apart | 6 inches, plant to plant |
| 4 x 4 bed (16 squares) | up to 64 bok choy plants |
| 4 x 8 bed (32 squares) | up to 128 bok choy plants |
| 3 x 6 bed (18 squares) | up to 72 bok choy plants |
That 6 inch, 4 per square spacing is the Plan My Garden planner’s, one 1 x 1 foot cell holding 4 plants. NC State Extension’s Plant Toolbox, covering the Brassica rapa Chinensis group that includes bok choy and pac choi, spaces or thins to the same 6 inches. Check other bed sizes with the square foot garden calculator. These counts are grid maximums, not a target for full-size heads: University of Minnesota Extension thins mature bok choy to 12 to 18 inches apart instead, which cuts the count to 1 per square, or a checkerboard of every other square for the widest heads, the same approach as full-size cabbage.
Why sources give 9, 4 or 1 bok choy plants per square foot
The numbers track harvest stage, not disagreement between sources.
| Source | Spacing | Per square foot |
|---|---|---|
| My square foot gardening chart (baby harvest) | 4 inches apart | 9 |
| Plan My Garden planner | 6 inches apart | 4 |
| NC State Extension’s Plant Toolbox | 6 inches apart | 4 |
| University of Minnesota Extension, dwarf or mature head | 12 inches apart | 1 |
| University of Minnesota Extension, full-sized head | 18 inches apart | No square match; a checkerboard is close |
My chart’s 9 per square is for a baby harvest picked young, so it packs in tight at 4 inches. The planner’s 4 per square, 6 inches apart, matches NC State Extension’s Plant Toolbox exactly. Let the head mature fully and University of Minnesota Extension widens that to 12 inches for dwarf varieties (1 per square) and 18 inches for full-sized ones, no square match, but close to a checkerboard’s diagonal spacing of about 17 inches (12 inches x 1.41).
Planting the square
- Sow seed 1/4 to 1/2 inch deep, the depth NC State Extension’s Plant Toolbox gives for the group, directly in the garden or started indoors a few weeks early.
- Start seed indoors 4 to 2 weeks before your last frost, direct sow 4 weeks before, or set transplants out 1 week before to on your last frost, the windows in the Plan My Garden planner.
- Thin to 4 inches apart, 9 per square, for the chart’s baby spacing, or 6 inches, 4 per square, for the planner’s standard spacing, the distance NC State Extension’s Plant Toolbox also uses.
- Keep the soil evenly moist. University of Minnesota Extension calls for about 1 inch of water a week during dry spells for the group.
Bolting: why a late summer sowing is more reliable
Bok choy bolts fast once the weather turns warm. University of Minnesota Extension warns that a late spring frost, or more than a week of nights below 50°F, is likely to push the plant to flower and stop growing once warm weather returns. Waiting until after your last frost avoids that but pushes maturity into hot weather instead, which the same source says narrows the leaves and thins the heads.
The fix is a different window: Minnesota Extension direct sows the group in the garden in July, timed to mature in the shortening days and cooler temperatures of September. Bok choy matures faster than Chinese cabbage, so even a late July planting is ready before cold weather, one of the fastest crops on my vegetable days to maturity chart at about 45 days, matching the planner.
When to plant bok choy
| Start indoors | 4 weeks before to 2 weeks before your last frost |
|---|---|
| Transplant out | 1 week before to on your last frost |
| Direct sow | 4 weeks before your last frost |
| Days to maturity | about 45 days, on my vegetable days to maturity chart; NC State Extension’s Plant Toolbox gives about 60 days to a full head |
| Frost tolerance | Semi-hardy on my vegetable frost tolerance chart, and on its list of crops to cover before a hard freeze; NC State Extension’s Plant Toolbox says the group tolerates light frost |
Turn the weeks into dates with the seed starting calendar, or enter your zip code on Plan My Garden to find your frost dates.
Harvest: whole heads or a few leaves at a time
You do not have to wait for a full head. University of Minnesota Extension and NC State Extension’s Plant Toolbox harvest bok choy the same two ways: pick the oldest, largest outer leaves a few at a time and let the inner leaves keep growing, or wait for the whole plant to reach a usable size and cut it at once. Dwarf varieties can be full-size at only 6 inches tall; full-sized ones reach about a foot, Minnesota Extension notes.
If a plant starts to bolt before you get to it, both sources agree: cut the whole head before the flowers open and use it as you normally would. Minnesota Extension adds that the flower stalk is edible, the same way you would use broccoli. Bok choy does not store the way cabbage does; Minnesota Extension says to use it within a week or two in the refrigerator.
Growing notes
The planner lists bok choy at about 12 inches tall, short enough for the front of a bed. NC State Extension’s Plant Toolbox notes it tolerates partial shade, as little as 2 hours of direct sun a day, though it grows slower without full sun. For a full-size head, checkerboard it like cabbage; for another fast crop on similar planner windows see turnip, and for another chart-vs-planner split see Swiss chard.
Quick questions
How many bok choy plants fit in a 4×8 raised bed?
Up to 128 at the standard 4 per square, 6 inches apart. Grown for a baby harvest at the chart’s tighter 9 per square, a 4×8 bed holds up to 288. A full-size head needs more room, down to 32 at 1 per square, or 16 in a checkerboard.
What is bok choy spacing in square foot gardening?
4 per square, 6 inches apart, the spacing the Plan My Garden planner uses. NC State Extension’s Plant Toolbox lists the same 6 inch distance for the crop group that includes bok choy and pac choi.
Can you plant bok choy closer together?
Yes, for a baby harvest. My square foot gardening chart lists baby bok choy at 9 per square, 4 inches apart, picked young for a few leaves rather than a full head.
Should you sow bok choy in spring or late summer?
Late summer is more reliable. University of Minnesota Extension warns that a late spring frost or a run of nights below 50°F can push bok choy to bolt once warm weather returns, so sowing in mid to late summer lets it mature in the cooler, shortening days of fall instead.
Do you harvest bok choy as a whole head or leaf by leaf?
Either. University of Minnesota Extension and NC State Extension’s Plant Toolbox both say you can pick the oldest, outermost leaves a few at a time, or wait and cut the whole head once it feels full. If the plant starts to bolt, cut it before the flowers open.
Let the planner place them
Skip the grid math. Plan My Garden is free to start: enter your zip code, draw your beds, pick bok choy and everything else you want to grow, and it places each plant at square-foot spacing and builds a planting schedule from your frost dates.
Related: Square Foot Gardening Chart · Seed Starting Calendar · How Many Cabbage Plants per Square Foot? · How Many Turnip Plants per Square Foot? · How Many Swiss Chard Plants per Square Foot?
