Lilac care — light, water, toxicity and hardiness
Lilac (Syringa vulgaris) wants full sun and a drink about every 7 days once established. It is hardy in USDA zones 3 to 7. It is safe to have around pets.
| scientific name | Syringa vulgaris |
|---|---|
| family | Oleaceae |
| category | shrub |
| plant type | perennial |
| light | full sun |
| water cadence days | 7 |
| min zone | 3 |
| max zone | 7 |
| frost tolerant | true |
| toxic to pets | false |
| edible | false |
How often should I water Lilac?
Water deeply during dry spells; lilacs dislike soggy soil.
Who eats it
Palatable to browsing animals such as deer: low. Palatable to grazing animals: low. Palatable to people: no.
What it needs
Its shade tolerance is medium. Its moisture use is medium. Its drought tolerance is medium. It wants at least about 30 inches of rain a year. Above roughly 50 inches of annual rain it struggles. It tolerates soil down to pH 5.8. It tolerates soil up to pH 7.8. Its fertility requirement is medium. Adapted to coarse, sandy soils: yes. Adapted to medium, loamy soils: yes. Adapted to fine, clay soils: yes. It needs at least 110 frost-free days. Its salt tolerance is medium. Its tolerance of chalky soil is high. Its fire tolerance is high. Fire resistant: no. It has been recorded down to -38°F. It suppresses neighbours chemically: no.
How it grows
It grows as a rhizomatous form. Its growth rate is moderate. Its lifespan is moderate. It puts on most of its growth in spring and summer. It spreads by seed at a slow rate. It spreads vegetatively at a moderate rate. It resprouts after damage: yes. Coppices: no. Its tolerance of hedging is high. At maturity it reaches about 20.0 feet. By twenty years it is about 20 feet. Its roots go down at least 14 inches. Its shape is erect. It holds its leaves through winter: no.
What it looks like
It blooms in late spring. The flowers are purple. Conspicuous in flower: yes. The foliage is green. The foliage texture is medium. In summer the canopy is dense in porosity. In winter it is moderate in porosity. Fall colour: no. The fruit or seed is brown. Fruit begins in summer. Fruit finishes by summer. It fruits medium. The fruit persists on the plant: yes. The fruit is conspicuous: no.
Growing more of it
Propagated by seed: yes. Propagated by cuttings: no. Propagated by container: yes. Propagated by bare root: yes. Propagated by bulb: no. Propagated by corm: no. Propagated by tubers: no. Cold stratification required: yes. Seedling vigour is medium. Commercial availability: routinely available.
Source: USDA PLANTS Database; US Cooperative Extension horticulture publications · ASPCA Toxic and Non-Toxic Plant List · 2026-09-02