Overview

Trachelium caeruleum 'Black Knight' is a bushy bedding in the genus Trachelium, part of the Campanulaceae family, with deciduous foliage. Trachelium caeruleum 'Black Knight' grows best in full sun, and tolerates loam and sand soils and any pH. Its UK hardiness is rated H2. Suggested uses include city and courtyard gardens, patio and container plants, cottage and informal garden, flower borders and beds, cut flowers and wall side borders.

About

Trachelium caeruleum 'Black Knight' is a bushy, deciduous cultivar of the Trachelium genus, which comprises perennial plants with small leaves and tubular flowers that bloom in summer. This cultivar thrives in full sun and suits both west- and east-facing aspects, tolerating exposed or sheltered conditions. It prefers fertile, moist but well-drained loam or sandy soils across a range of pH levels. Hardy to UK zone H2, 'Black Knight' is suitable for city gardens, patios, flower borders, and as cut flowers, offering seasonal interest in spring and summer.

Growing conditions

Best soil and position for Trachelium

Sunlight
Full sun
Soil type
Loam, Sand
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Moist but well-drained
Aspect
West-facing, East-facing
Exposure
Exposed, Sheltered
UK hardiness
H2

Plant details

Trachelium caeruleum 'Black Knight' size, habit and characteristics

Plant type
Bedding, Conservatory Greenhouse, Herbaceous Perennial, Annual Biennial
Habit
Bushy
Foliage
Deciduous
Suggested uses
City and courtyard gardens, Patio and container plants, Cottage and informal garden, Flower borders and beds, Cut flowers, Wall side borders

Care notes

Pruning and caring for Trachelium caeruleum 'Black Knight'

Propagation
Seed sown at 16°C in spring
Pest resistance
Generally pest-free
Disease resistance
Generally disease-free

Frequently asked questions

Where is the best place to plant Trachelium caeruleum 'Black Knight'?

Trachelium caeruleum 'Black Knight' prefers full sun. It suits exposed and sheltered positions.

What soil does Trachelium caeruleum 'Black Knight' need?

Trachelium caeruleum 'Black Knight' grows best in loam and sand soil. It is happy in soil of any pH. Aim for soil that stays moist but well-drained.

Is Trachelium caeruleum 'Black Knight' hardy in the UK?

Trachelium caeruleum 'Black Knight' has an RHS hardiness rating of H2, meaning it is tender, tolerating 1–5°C, and needs frost-free protection over winter.

How do I propagate Trachelium caeruleum 'Black Knight'?

Seed sown at 16°C in spring.

More in the Trachelium genus

Browse all Trachelium