Garden Phlox — Growing reference
| Scientific name | Phlox paniculata |
|---|---|
| Seed germination (days) | 25–30 |
| Soil temperature for germination (°C) | 12.8–18.3 |
| First harvest or flowering (days) | 90–120 |
| Measured from | Transplant |
| Plant spacing (cm) | 45.7–61 |
| Mature height (cm) | 61–121.9 |
| Mature spread (cm) | 45.7–61 |
| USDA hardiness zones | 4–8 |
| Light | Partial sun |
| Water | Moderate |
| Sowing method | Division |
Growing directions
Plant divisions in moist, organically rich, well-drained soil in full sun to partial shade, spacing 18–24 inches apart with excellent air circulation; garden phlox is a native Eastern North American perennial that produces large, rounded heads of fragrant flowers in pink, red, white, lavender, or bicolor shades from midsummer into fall — one of the best summer perennials for cutting. Powdery mildew is the primary challenge: thin stems to 5–7 per clump, water at the base only, and choose mildew-resistant cultivars such as 'David' (white) or 'Robert Poore' (purple). Deadhead faded flower heads to prevent seedlings that revert to magenta. Divide every 3 years in early spring to maintain vigor and prevent the center of the clump from dying out.
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.
OpenPlantDB · phlox-paniculata
Source & verification
OpenPlantDB · CC0