Climate matters. This page is a practical baseline. Confirm cultivar, local frost/heat conditions, mature size and regional restrictions before planting.
Radish — Growing reference
| Scientific name | Raphanus sativus |
|---|---|
| Seed germination (days) | 3–7 |
| Soil temperature for germination (°C) | 7.2–29.4 |
| First harvest or flowering (days) | 22–35 |
| Measured from | Seed |
| Plant spacing (cm) | 5.1–7.6 |
| Mature height (cm) | 15.2–30.5 |
| Mature spread (cm) | 5.1–7.6 |
| USDA hardiness zones | 2–11 |
| Light | Full sun |
| Water | Moderate |
| Sowing method | Direct sow |
Growing directions
Sow seed 1/2 in deep in cool, well-drained soil at 10-day intervals for a steady supply. Radishes bolt quickly in heat or long days, so spring and fall are the prime windows. Thin to 2 in as soon as seedlings are up to prevent overcrowding, which causes lanky tops and small or misshapen roots. Pull spring types at 3/4 to 1 in diameter before they become hot and pithy.
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