How does temperature affect cabbage harvesting?
Written by
Liu Xiaohui
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Temperature has a significant impact on cabbage quality and the optimal timing of harvest. Temperatures above 80°F will hasten the onset of bolting and splitting. In contrast, cold temperatures, including frost, will improve flavor in the colder-tolerant cabbages. Sudden fluctuations in temperature lead to changes in the texture and storage ability of cabbage. The temperature impacts of our harvest decisions are crucial, as we aim to maximize quality when harvesting cabbage.
Heat Stress Response
- Bolting occurs above 80°F (27°C)
- Splitting risk increases with sudden temperature spikes
- Immediate harvest preserves quality during heat waves
Cold Tolerance Levels
- Savoy survives down to 15°F (-9°C)
- Frost converts starches to sugars improving flavor
- Green varieties tolerate 25°F (-4°C)
Fluctuation Management
- Harvest during stable weather periods
- Use row covers for 10-15°F temperature modulation
- Mulch regulates soil temperature effectively
As heads near maturity, monitor forecasts daily. Placement of wireless thermometers at canopy height will provide accurate temperature readings, Harvest heads when the temperature is cool and below 70 °F, preferably in the morning. Avoid harvesting when temperatures increase in the middle of the day, as heat causes plant stress and decreases post-harvest quality.
Take steps to protect against extreme temperatures. In warm temperatures (above 75°F), place 30% shade cloth over plants. To provide cold temperature protection, place floating row covers before frost. These measures create microclimates that should extend growing conditions by 10-15 degrees.
Alter harvest schedules according to the variety's cold tolerance. Savoy cabbages develop a sweeter flavor after a light frost, making them ideal for fall gardens. Tender Napa varieties must be harvested before the temperature drops below 30°F. Always cut the stem 1-2 inches above the soil.
Condition cabbage according to the temperature of harvest. If the heads were harvested in heat, they need to be cooled quickly in an ice bath. Cabbage harvested in frost will last longer in root cellars. When storing cabbage, maintain storage temperatures between 32°F and 40°F, regardless of field conditions.
Read the full article: 5 Signs When to Harvest Cabbage
