How long does onion curing take?
Written by
Liu Xiaohui
Reviewed by
Prof. Charles Hartman, Ph.D.The duration for onion curing can vary depending on technique, but curing most commonly takes 2-4 weeks. I schedule this during each growing season. Proper curing builds protective skins and seals necks to prevent rot. If you rush this process, you jeopardize the storage potential of the onion.
Field Curing
- Requires 2-4 sunny days at 75-90°F. Lay bulbs in single rows with tops covering them. I do this during dry weather watching for rain threats. Turn bulbs daily for even drying.
Indoor Curing
- Takes 2-4 weeks with 60% humidity and constant airflow. Use mesh trays in well-ventilated spaces. I add fans for circulation preventing moisture buildup. Check humidity with hygrometers.
Forced Air Curing
- Completes in 10-14 days using specialized dehydrators. Maintain 80°F with gentle airflow. I reserve this for humid climates where traditional methods fail. Requires equipment investment.
Humidity control makes or breaks curing. Indoor spaces require a consistent humidity level of 60%. I use dehumidifiers in damp basements. Too dry stops skin formation, while too wet causes mold to grow. Monitor daily.
Temperature consistency prevents problems. Maintain a temperature of 75-90°F to support enzyme activity and facilitate the creation of protective compounds. I use thermometers in curing areas; fluctuations below 70°F slow curing, extending the process.
Mold Prevention
- Increase spacing between bulbs. Rotate positions daily. Add fans if condensation appears. I catch mold early by inspecting neck areas every 2 days.
Slow Drying Solutions
- Reduce humidity 5-10%. Increase temperature 5°F. Check for airflow blockages. I've fixed this by repositioning fans toward bulb piles.
Storage varieties cure differently from sweets. Copra onions need 3-4 weeks while Vidalias cure in 10-14 days. I adjust schedules accordingly. Denser bulbs always require more time.
Read the full article: 7 Essential Signs for When to Harvest Onions
