Yellow Onion — Growing reference
| Scientific name | Allium cepa |
|---|---|
| Seed germination (days) | 10–14 |
| Soil temperature for germination (°C) | 15.6–23.9 |
| First harvest or flowering (days) | 100–120 |
| Measured from | Transplant |
| Plant spacing (cm) | 10.2–15.2 |
| Mature height (cm) | 45.7–61 |
| Mature spread (cm) | 10.2–15.2 |
| USDA hardiness zones | 2–11 |
| Light | Full sun |
| Water | Moderate |
| Sowing method | indoor-start |
Growing directions
Start seeds or transplant pencil-thick seedlings in full sun in well-drained, fertile, neutral to slightly acidic soil early in spring; yellow onions are the most versatile and widely grown culinary onion, with their characteristic balance of sulfurous pungency and underlying sweetness that mellows to a rich sweetness when cooked, making them essential in virtually every cuisine worldwide. Long-day varieties (required for zone 3–6 where summer days exceed 14 hours) include 'Copra' and 'Patterson'; short-day varieties (zone 7–10) include 'Texas 1015', 'Candy', and 'Georgia Sweet'. Harvest when most tops have fallen over naturally; cure in a warm, dry, well-ventilated spot for 2–4 weeks. Well-cured yellow onions store for 3–6 months.
Source and local conditions
Typical planning ranges from OpenPlantDB (CC0). Cultivar, climate, season and growing method can change these values. Confirm the seed label and local guidance before planting.
Source & verification
OpenPlantDB · CC0