Chinese Broccoli illustration

Growing Chinese Broccoli in Zone 4b

Zone 4b has cold winters and a moderate growing season. Timing is key for Chinese Broccoli in this zone. Last frost: May 1. First frost: Oct 5.

Planting Calendar

Indoor
Outdoor
Harvest
Mar 20Oct 5

Season: May 1 – Oct 5 (157 days)

Zone4b
Last FrostMay 1
First FrostOct 5
Season Length157 days
Days to Harvest60
SunFull Sun
Frost ToleranceHeavy
Spacing4/sqft (6" apart)

When to Plant Chinese Broccoli in Zone 4b

Start Seeds Indoors: Mar 20

Start Chinese Broccoli seeds indoors around Mar 20 (6 weeks before last frost). Optimal germination temperature: 75°F. Germinates in 5–10 days.

Transplant Outdoors: May 15

Transplant Chinese Broccoli seedlings outdoors after May 15. Wait until soil temperature reaches 50°F. Space plants at 4/sqft (6" apart). Harden off plants for a week before moving outside.

Harvest: Jul 14

First harvest approximately Jul 14 (~60 days from transplant). Continue harvesting until first frost (Oct 5).

Fall Planting: Jul 13

For a fall harvest, plant Chinese Broccoli around Jul 13 (12 weeks before first frost).

Frequently Asked Questions

When should I plant Chinese Broccoli in Zone 4b?

Start Chinese Broccoli seeds indoors around Mar 20. Transplant outdoors after May 15. Expect first harvest around Jul 14.

What is the last frost date for Zone 4b?

The average last spring frost date for Zone 4b is May 1. The first fall frost averages Oct 5, giving a 157-day growing season.

Can I grow Chinese Broccoli in Zone 4b?

Yes. Chinese Broccoli needs 60 days to harvest. Zone 4b has a 157-day growing season, which is sufficient.

What is the best month to plant Chinese Broccoli in Zone 4b?

The best time to start Chinese Broccoli in Zone 4b is Mar. Begin seeds indoors around Mar 20, then transplant outdoors after the last frost date of May 1.

How long does Chinese Broccoli take to harvest?

Chinese Broccoli takes approximately 60 days from planting to harvest. In Zone 4b, expect your first harvest around Jul 14.

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Track Chinese Broccoli from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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