🌿 Onion – Outdoor Growing Guide

Frost-hardy – avoid waterlogging, ripens in dry conditions.

Frost Sensitivity
Low
Min. Night Temperature
2°C
Safe transplanting threshold
Optimal Day Temperature
10–28°C
Ideal daytime range
Planting Season
Early Spring
Typical planting window

📅 When to Plant Onion?

Onion (also known as Zwiebel) belongs to the Vegetables category and is suitable for outdoor planting from Early Spring onwards.

Use the Growing Temperature Sum (GTS) as a guide: Onion can be safely transplanted once the local GTS has passed the threshold for Early Spring and no frost is expected. GrowPilot.guide calculates the current GTS for your location automatically.

🗓️ Tip: Always check the 10-day weather forecast before planting outdoors. The GTS is a helpful guide but does not replace a frost check for your specific area.

❄️ Frost Sensitivity & Protection

Onion is frost-hardy and withstands moderate freezing temperatures well. Can be planted early in spring once the ground is workable. Ideal minimum night temperature: 2°C.

🌡️ Optimal Temperatures

Onion grows best at daytime temperatures between 10°C and 28°C. Night temperatures should not fall below 2°C.

🍄 Mold & Rain Tolerance

Onion shows moderate sensitivity to mold. Take precautions during extended rain or very high humidity – good ventilation is important.

Rain sensitivity: High – Prolonged rain can cause damage – protection with a film cover or roof overhang is recommended.

📱 Plan with GrowPilot.guide

GrowPilot.guide calculates the current Growing Temperature Sum (GTS) for your location, shows the phenological season and gives you a daily personalised analysis – including frost warnings, mold risk and optimal planting time for Onion.

Open GrowPilot.guide for your personalised planting calendar — automatically adjusted to your climate, wherever you are in the world.

🌱 Plan Onion with GrowPilot.guide

Get a daily personalised weather analysis for Onion – with GTS, frost warnings and planting recommendations for your location worldwide.

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📚 Grow Guides for Onion

Expert growing knowledge to help you cultivate Onion successfully:

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