Syringa vulgaris 'Cavour'

RHS Plant Profile

lilac 'Cavour'

Shrubs

A deciduous shrub, to around 3m high, with an upright to spreading habit and oval to heart-shaped, slightly glossy green leaves. Upright clusters of fragrant, violet-blue flowers are produced in late spring and early summer

Position

Full sun, Partial shade

Soil Types

Chalk, Clay, Loam, Sand

Max Height

2.5-4 metres

Max Spread

2.5-4 metres

Size

Time to Maturity: 5–10 years
Max Spread: 2.5-4 metres
Max Height: 2.5-4 metres

Growing Conditions

Chalk Clay Loam Sand

Moisture: Moist but well–drained or Well–drained
pH: Alkaline or Neutral

Position

Full sun Partial shade

Aspect: South–facing or West–facing
Exposure: Exposed or Sheltered
Hardiness

Hardiness Ratings

All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

H1A: under glass all year (>15C)
H1B: can be grown outside in the summer (10 - 15)
H1C: can be grown outside in the summer (5 - 10)
H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
H4: hardy through most of the UK (-10 to -5)
H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
H6: hardy in all of UK and northern Europe (-20 to -15)
H7: hardy in the severest European continental climates (< -20): H6

Colour & Scent

Fragrance Flower

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Oleaceae
Native to GB/Ireland: No
Foliage: Deciduous
Habit: Spreading branched, Bushy
Genus: Syringa can be deciduous shrubs or trees, with simple, entire or rarely pinnate leaves and conical panicles of small, very fragrant, 4-lobed tubular flowers in late spring or early summer
Name Status: Accepted

How to Grow

Cultivation

Thrives in well-drained, fertile, humus-rich alkaline to neutral soils. Will tolerate some light shade but flowering is best in full sun. Mulch well in spring

Propagation

Propagate by softwood cuttings or by layering in early summer, by grafting in winter or by chip budding in midsummer

Suggested planting locations and garden types

Cottage and informal garden
Low Maintenance
Flower borders and beds

Pruning

Minimal pruning required, trim immediately after flowering if necessary (see pruning group 1)

Pests

May be susceptible to lilac leaf-mining moth, thrips and willow scale insects

Diseases

May be susceptible to lilac blight, honey fungus, phytophthora, powdery mildews and bacterial canker