Vigorous southeast European deciduous shrub with dense conical panicles of small intensely fragrant lilac, purple, white, or pink flowers in late spring. The signature fragrance of cottage gardens worldwide.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 3–7 | −40 °C to −12.2 °C | Plant tolerates down to this zone |
| RHS hardiness rating | H7 | down to −20 °C | Plant needs at least this level of cold tolerance |
| Canadian plant hardiness zone | Zone 3–7 | −34 °C to −7 °C | Plant tolerates down to this zone |
| Australian (ANBG) zone | Zone 1–4 | −15 °C to 5 °C | Plant tolerates down to this zone |
About Common lilac
Common lilac is a member of the olive family, which is not obvious until it flowers and the tubular blooms are examined closely. It suckers freely from the base and is very long-lived; abandoned garden sites often show lilacs persisting long after the buildings have gone. Flower buds are formed the previous summer, so pruning at the wrong point in the year removes the coming display. Unlike most highly scented shrubs it is genuinely hardy in cold climates and, unusually, tends to flower better in soil that is neutral to slightly alkaline.
Growing notes
- Plant where the fragrance can be enjoyed close at hand — pour out the strongest fragrance of any common spring shrub
- Needs winter chilling to flower well — unreliable in mild climates, best in zones 7 and cooler
- Suckers freely on its own roots — grafted plants stay tighter, own-root specimens form thickets
- Cut back hard after flowering for a strong next-year bloom — flowers on previous year’s wood
Categories
Related plants
Cross-check Common lilac against your zones