Climate matters. This page is a practical baseline. Confirm cultivar, local frost/heat conditions, mature size and regional restrictions before planting.
Zinnia — Growing reference
| Scientific name | Zinnia elegans |
|---|---|
| Seed germination (days) | 5–7 |
| Soil temperature for germination (°C) | 21.1–26.7 |
| First harvest or flowering (days) | 60–70 |
| Measured from | Seed |
| Plant spacing (cm) | 15.2–45.7 |
| Mature height (cm) | 30.5–121.9 |
| Mature spread (cm) | 20.3–45.7 |
| USDA hardiness zones | 3–11 |
| Light | Full sun |
| Water | Moderate |
| Sowing method | Direct sow |
Growing directions
Sow seed 1/4 in deep directly in the garden once frost risk is past and soil is warm. Pinch seedlings at 6 in tall to promote branching and a fuller plant with more stems for cutting. Cut flowers frequently to the next set of leaves to stimulate continuous bloom through summer. Avoid overhead watering to reduce powdery mildew; water at the base.
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