Growing guide · Shrubs

Buddleja hybrid

How to grow Butterfly Bush 'Monarch® Blue Knight'.

Butterflies show up. Every single afternoon.

Light
Full sun
Water
Low
Zones
5–9
Size
3–4 ft tall, 4–6 ft wide
Spacing
4–5 ft apart.
Pets
Not on the ASPCA pet-safe list; keep it out of reach
See sizes · from $46.99
Rounded shrub with long spikes of lavender and blue-purple flowers

Light

Full sun. In shade it gets leggy and blooms thinly.

Water

Water weekly the first summer. Established plants are drought tolerant.

Planting and soil

Plant in spring so it establishes before winter. Avoid wet, heavy soil.

Feeding

Light feeding in spring, or none in decent soil.

Pruning

In spring, after buds break, cut stems back to 12–18 in. It blooms on new wood.

Through the year

Late to leaf out; do not give up on it in April. Blooms July to frost.

If something's off

Wet winters kill more butterfly bushes than cold. Deadhead to limit seedlings; Buddleja davidii types are invasive in some western and southeastern states.

Plays well with

Plant it with friends.

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Why we stock it: Big late-season color and pollinator traffic in a shrub-border-friendly size.

That's everything we know about growing it. Thanks for reading.

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