Chinese Cabbage — GDD Requirements by Growth Stage

Overview

This report surveys GDD required at each major stage of Chinese cabbage (Brassica rapa var. pekinensis)—seedling, rosette, folding, heading, and flowering—from Japanese and international sources. Direct stage-specific GDD is rarely reported; estimates use total GDD, stage duration, optimal/minimum temperatures, and standard calculation methods.

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GDD Calculation Basics

• Formula: GDD = Σ (daily mean temperature − 7°C); days below base count as 0.
• Base temperature 7°C is most common[1][2][3][4][5][6][7][8][9].
• Total transplant to harvest: ~650–1,000°C·days (varies by system and cultivar)[3][7][9][10][11].

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GDD by Growth Stage

Seedling (sowing to ~5–6 true leaves)

• ~20 days nursery; optimal 20–25°C (germination 15–30°C)[2][4].
• Estimate: (20−7)×20 ≈ 260°C·days.
• Below 13°C for 10+ days increases bolting risk[4][6][12].

Rosette (outer leaf expansion)

• ~15–20 days after seedling; optimal 18–22°C[2][4].
• Estimate: (20−7)×20 ≈ 260°C·days; cumulative ~520°C·days.

Folding (initial heading)

• Often ~40–45 days after sowing; optimal ~16–17°C[2][4][5].
• Cumulative ~500°C·days to folding; +100–150°C·days for transition.
• Heading stops below 4°C[2][4][6].

Heading (head enlargement)

• Optimal mean 15–18°C; ~10–30 days[2][3][4][6].
• Estimate: (16−7)×25 ≈ 225°C·days; total sowing to harvest ~650–1,000°C·days[3][7][8][9][10][11].

Flowering (bolting)

• Usually avoided in market production; induced by seedling cold (<13°C for 10+ days) plus spring warming[4][6][12].
• After flower initiation: ~50 days at 15°C → (15−7)×50 = 400°C·days (reference only).

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GDD Summary Table (Estimates)

Stage	Duration	Example mean temp	Stage GDD	Cumulative GDD
Seedling	20 days	20°C	260°C·days	260°C·days
Rosette	20 days	20°C	260°C·days	520°C·days
Folding	10 days	18°C	110°C·days	630°C·days
Heading	25 days	16°C	225°C·days	~850°C·days
Flowering	50 days	15°C	400°C·days	(reference: >1,200°C·days at flowering)

Try it in your region

See how these GDD requirements apply to your local weather data. Simulate Chinese Cabbage cultivation →

• Stage transitions are guides; adjust for region, cultivar, and weather.
• Total crop cycle often 65–90 days and 650–1,000°C·days[3][7][9][10][11].

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Practical Significance

• Stage GDD aids growth diagnosis and harvest timing; supports sowing/transplant decisions and bolting avoidance[2][4][5][6].
• Account for weather variability, cultivar traits, pests, and soil conditions.

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Conclusion

Although direct stage GDD values are rarely published, estimates from duration, temperature, and cumulative GDD (base 7°C; ~650–1,000°C·days to heading harvest) are useful for field diagnosis and timely management.

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Sources

[1] Banraisha Hakusai cultivation notes Part 2 https://www.banraisha.co.jp/saien/yasai/05/hakusai/index.html
[2] Chinese cabbage growth stages PDF - BSI Bioscience https://bsikagaku.jp/cultivation/chinese+cabbage.pdf
[3] Takii Chinese cabbage cultivation manual PDF https://www.takii.co.jp/tsk/tools/y_manual_pdf/y_manual_hakusai.pdf
[4] Sakata Chinese cabbage cultivation https://sakata-tsushin.com/lesson-vegetable/detail_15/
[5] BSI Bioscience fertilizer application PDF http://bsikagaku.jp/f-fertilization/chinese cabbage.pdf
[6] JASTA Chinese cabbage information PDF https://www.jasta.or.jp/active/download/docs/hakusai.pdf
[7] Tanba Sasayama vegetable harvest GDD table https://weathernew.sasayama.jp/sekisan3/
[8] JA Aichi Mikawa home garden Chinese cabbage https://www.ja-aichimikawa.or.jp/garden/hakusai.php
[9] Kanagawa Agricultural Research Center winter Chinese cabbage late planting https://www.pref.kanagawa.jp/documents/27459/165-1-hakusai.pdf
[10] Harvest-timer vegetable GDD list https://harvest-timer.com/temperature/
[11] JA Hare no Kuni Okayama home garden Chinese cabbage https://www.ja-hareoka.or.jp/agri_food/kateisaien/2021/017/index.html
[12] BSI Bioscience Chinese cabbage cultivation PDF https://bsikagaku.jp/cultivation/chinese%20cabbage.pdf