shrub RHS Award

Black Knight Butterfly Bush

Name: Black Knight Butterfly Bush
Brand: Buddleia
Availability: InStock

Buddleia davidii 'Black Knight'

$85.00

Expertly Curated

Real-Time Pricing

Loved by Designers

Essentials

At a Glance

Plant Type

Shrub

Height

84 inches

Width

60 inches

Light

Full Sun

Zones

5, 6, 7, 8, 9

Water

Low to medium

Humidity

Adaptable, prefers good air circulation

Lifespan

Short-lived shrub, 10-15 years

Native To

China, Japan

Toxicity

Non-toxic

The Story

Plant Bio

Buddleia davidii is a fast-growing, deciduous shrub known for its long, arching panicles of fragrant flowers that are highly attractive to butterflies. It often dies back to the ground in colder climates. 'Black Knight' is one of the darkest flowered cultivars, featuring rich, deep violet-purple flowers in dense, 6-10 inch long, elongated clusters.

Bloom Period:

EarlyLate

Uses & Benefits:

Provides a dramatic splash of deep color with its fragrant, dark purple flower spikes throughout the summer. Its arching habit adds graceful form to the garden.

Its fast-growing nature makes it useful for quickly filling in new garden spaces or creating a temporary summer screen.

It is famously one of the best plants for attracting a wide variety of butterflies, as well as bees and other pollinators, providing a crucial mid- to late-summer nectar source.

Marketplace

Where to Buy

Sooner Plant Farm

1+ Gal Pot

In Stock$85.00

Shipping costs Year-round shipping Free shipping

Planting

How to Grow

Select a site in full sun with excellent drainage.
Amend heavy clay soils with compost to improve drainage.
Plant at the same depth as its nursery container.
Water regularly until established, then only during drought.
Avoid heavy fertilization, which promotes leaves over flowers.
Deadhead spent flowers to encourage reblooming and reduce self-seeding.

Pro Tip

Cut back hard to 12 inches in early spring to promote vigorous new growth and abundant flowers.

Keep It Thriving

Care Guide

Do

Provide at least 6 hours of direct sun daily.
Ensure soil is very well-drained.
Prune back hard in early spring after the last frost.
Deadhead spent blooms to promote more flowers.

Don't

Do not plant in wet, boggy soil.
Do not overwater once the plant is established.
Avoid fertilizing, as it can reduce flowering.
Do not plant where it is considered invasive without choosing a sterile cultivar.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Deadhead
Pest Check
Prune

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Pollinator garden centerpieceMixed border back-of-the-border plantFast-growing summer color

Companion Plants

Echinacea purpurea Rudbeckia fulgida Salvia nemorosa Panicum virgatum Achillea millefolium

Multiply

Propagation Methods

Good to Know

Common Questions

Black Knight Butterfly Bush questions

What zones can Black Knight Butterfly Bush grow in?

Black Knight Butterfly Bush is hardy in USDA Zones 5–9. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Black Knight Butterfly Bush deer resistant?

Yes — Black Knight Butterfly Bush is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does Black Knight Butterfly Bush bloom?

Black Knight Butterfly Bush typically blooms in mid-summer through early fall. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Black Knight Butterfly Bush need full sun?

Black Knight Butterfly Bush does best in full sun (6+ hours).

Is Black Knight Butterfly Bush drought tolerant?

Yes — once established (usually after the first full season), Black Knight Butterfly Bush handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.