Bok choy is the crisp, mild Asian green that Zone 7 grows best in the cool shoulders of the year — spring and, especially, autumn. This guide covers when to plant bok choy zone 7 in detail: the sowing, transplanting and harvest windows for USDA Zone 7, plus spacing, soil, water, companions, pests and storage — all based on USDA zone averages and standard published crop ranges.
Zone 7 covers areas with average annual minimum temperatures of 0 to 10°F. The average last spring frost falls in the Mar 15–Apr 1 range and the average first autumn frost in the Nov 1–15 range. These are USDA zone averages, not exact dates for any one garden — check your local extension service and the forecast before planting tender crops outside. The frost-free season runs roughly seven months, from late March into early November,
When to plant bok choy in Zone 7
Sow bok choy in February to March indoors, or direct-sow in March to April, for a spring crop ready in 45–60 days. But the autumn crop is the reliable one in Zone 7: spring-sown bok choy bolts at the first hot spell, while August to September sowings mature into cool weather and form full, crisp heads.
The table below puts the whole season on one page. All dates are ranges worked back from the Zone 7 frost averages (Mar 15–Apr 1 last frost, Nov 1–15 first frost) and the crop's published days to maturity (45–60 days). Use the frost date calculator to check the averages for your own area, and confirm them with your local extension service.
| Stage | Zone 7 window | Notes |
|---|---|---|
| Start indoors | Feb–Mar for spring; July–Aug for autumn | Germination takes 7–10 days |
| Direct sow outdoors | Mar–Apr, and Aug–Sep for the autumn crop | Sow into moist, prepared soil |
| Transplant outdoors | Apr, and Sep for autumn plants | Harden seedlings off first |
| First harvest | May–June and Oct–Nov, 45–60 days after sowing | 45–60 days to maturity |
| Autumn / second sowing | Autumn sowing avoids bolting — sow Aug–Sep | Count back from the first frost |
Starting and planting
Space plants 8–12 inches apart in rich, moisture-holding soil with a pH of 6.0–7.5. Bok choy likes part shade in warm weather and steady water — drought triggers bolting. Mulch to keep the soil cool and moist, and keep the bed weed-free while plants are young.
Before sowing, fork the bed over, remove weeds and stones, and dig in well-rotted compost. Bok Choy grows best at a soil pH of 6.0–7.5 — test your soil through your local extension service before amending it.
Spacing, sun and soil
Space plants 8–12 inches apart. Crowded plants compete for light, water and nutrients, stay small, and invite disease through poor airflow, so thin seedlings to the final spacing once they are established.
Give this crop full sun where you can, but it tolerates part shade — and in a Zone 7 summer, afternoon shade is often a benefit rather than a drawback, slowing bolting and keeping leaves tender.
Soil should be deep, fertile and free-draining, with a pH of 6.0–7.5. Heavy clay improves with compost and organic matter, and raised beds help where drainage is poor.
Watering
Water needs are moderate: aim for steady, even moisture rather than feast-and-famine watering. About an inch of water a week from rain or irrigation is a useful guide in most Zone 7 summers, more in hot, dry spells. Water at the base of the plant in the morning, mulch to hold moisture, and avoid wetting the leaves, which invites disease.
Companion planting
Good companions for bok choy include marigolds, basil, onions, lettuce. Planting companions nearby can help with pest confusion, pollination and making the most of bed space — marigolds, for example, are a classic companion across the vegetable garden. The companion planting finder can suggest combinations for your whole bed. Avoid planting bok choy where others of the same family (Brassicaceae) grew last year: rotate crops each season to reduce soil-borne disease and pest build-up.
Common pests and problems
Watch for cabbage worms, aphids, flea beetles, slugs. - Cabbage Worms — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
- Aphids — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
- Flea Beetles — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
- Slugs — inspect weekly; hand-pick or wash off with water, and encourage natural predators.
Beyond pests, the main problems are weather-related: a late frost after transplanting, drought at a critical stage, or waterlogged soil after heavy rain. Cover tender plants with frost cloth if a late frost threatens, and mulch to even out soil moisture.
Harvest and storage
Harvest from May to June for spring plants and October to November for autumn plants, cutting whole heads at the base or picking outer leaves as needed. Heads should feel firm and crisp; if a flower stalk appears, harvest immediately and use the leaves before they turn bitter.
Bok choy keeps for about a week in the fridge. It stir-fries, soups and pickles well, and autumn heads can stand in the garden under a light cover into early winter.
The classic Zone 7 mistake with bok choy is spring-sowing too late. A May sowing bolts before it heads — sow in early spring, or wait and sow in August for the dependable autumn crop.
Frequently asked questions
When should I plant bok choy in Zone 7?
Sow bok choy in February to March indoors, or direct-sow in March to April, for a spring crop ready in 45–60 days. Work from the table above, using the average last frost (Mar 15–Apr 1) and first frost (Nov 1–15), with 45–60 days to maturity. These are USDA zone averages, not exact dates for any one garden — check your local extension service and the forecast before planting tender crops outside.
How much sun does bok choy need in Zone 7?
Part Shade — at least six hours of direct sun a day where possible. Give it the sunniest spot you have.
What soil pH does bok choy prefer?
A pH of 6.0–7.5. Test your soil before amending it, and add compost to improve structure whatever the pH. Your local extension service can test a sample and recommend amendments.
What pests attack bok choy in Zone 7?
The most common are cabbage worms, aphids, flea beetles, slugs. Inspect plants weekly, hand-pick larger pests, wash small ones off with water, and keep the bed clean and well-spaced so air circulates.
How do I store bok choy after harvest?
Bok choy keeps for about a week in the fridge. It stir-fries, soups and pickles well, and autumn heads can stand in the garden under a light cover into early winter.
See the Zone 7 September planting guide for what else to sow and plant in the same month, browse the full planting calendar, and try the Seed Starting Calculator to plan your dates. For a related crop, see when to plant kohlrabi in Zone 7.