How do you root butterfly bush cuttings? Take butterfly bush cuttings as softwood in early summer or semi-ripe stems from July to September, trim them to about 2 to 4 inches (5–10 cm) below a node, remove the lower leaves, and root them in moist compost under a clear cover. The Royal Horticultural Society lists both methods for buddleja, and its softwood method roots in about 2 to 4 weeks.
Key takeaway: Butterfly bush (Buddleja davidii) roots readily, and University of Missouri Extension lists softwood cuttings, hardwood cuttings and simple layering as options. Before you multiply it, check local rules: University of Maryland Extension classifies butterfly bush as invasive because it spreads into natural areas by seed.
| Method | Timing | Source |
|---|---|---|
| Softwood butterfly bush cuttings | Early summer | RHS |
| Semi-ripe cuttings | July–September | RHS |
| Hardwood cuttings | Dormant season | University of Missouri Extension |
| Simple layering | Growing season | University of Missouri Extension |
| Invasive status | Invasive in Maryland; spreads by seed | University of Maryland Extension |
When Should You Take Butterfly Bush Cuttings?
Early summer for softwood, mid to late summer for semi-ripe. The RHS buddleja guide says buddlejas are propagated by softwood or greenwood cuttings in early summer and by semi-ripe cuttings, which it defines as stems grown this season taken from July to September. The University of New Hampshire Extension also lists butterfly bush among shrubs propagated from softwood cuttings.
- Softwood: soft, fast-growing tips in early summer.
- Semi-ripe: firmer current-season stems, July–September.
- Hardwood: dormant stems, per Missouri Extension.
How Do You Take Softwood Butterfly Bush Cuttings?
Follow the RHS softwood method. Collect non-flowering shoots early in the day while they are full of water, remove up to 4 inches (10 cm) of shoot and keep the material in a clean, labeled plastic bag. Trim below a node to make a cutting about 2 to 4 inches (5–10 cm) long, remove the lower leaves and pinch out the soft tip.
- Pick non-flowering shoots in the morning.
- Bag them right away to stop wilting.
- Trim just below a node to 2–4 inches (5.1–10 cm).
- Remove lower leaves and the soft tip.
- Dip in rooting hormone if you like.
- Insert into moist, free-draining compost.
Do Butterfly Bush Cuttings Need Rooting Hormone?
It is optional but useful. UNH Extension recommends dipping the base of softwood cuttings in rooting hormone for faster and better rooting, then inserting the cutting up to the remaining leaves in the medium. The RHS notes that cutting just below a node targets a concentration of hormones that stimulates root production. Our rooting hormone guide compares products.
How Do You Keep Butterfly Bush Cuttings Humid?
Cover them, but let them breathe. The RHS says a plastic bag over the pot in a warm spot will do if you have no propagator, but remove the bag to ventilate at least twice a week for 10 minutes. Keep the compost moist and shade cuttings from bright sun. Our propagation box guide shows a simple enclosure.
How Long Do Butterfly Bush Cuttings Take to Root?
Butterfly bush cuttings usually root in a few weeks. The RHS says softwood cuttings are well rooted in about 2 to 4 weeks, while UNH Extension says most shrubs root within 3 to 6 weeks and can become small plants in 6 to 8 weeks. Semi-ripe and hardwood cuttings usually take longer than softwood. A gentle tug that meets resistance means roots have formed.
- Softwood: about 2–4 weeks (RHS).
- Most shrubs: 3–6 weeks (UNH).
- New plants: about 6–8 weeks (UNH).
Is Butterfly Bush Invasive?
In many areas, yes. University of Maryland Extension states that butterfly bush is invasive and spreads into natural areas by seed, with each flower producing a capsule of tiny seeds dispersed by wind and water. It advises against planting it and notes that Maryland regulates invasive plant sales. Some cultivars are marketed as sterile, but UMD says listing rules apply to all cultivars unless exempted.
- Check your state’s invasive plant list first.
- Deadhead spent flowers before seed sets.
- Consider native shrubs for pollinators.
Can You Root Butterfly Bush Cuttings in Water?
The sources here describe compost or soilless media, not water. Soft cuttings of many shrubs will form roots in a jar, but water roots can struggle when moved to soil. If you try it, change the water often and pot up once roots appear. Our water vs soil propagation guide explains the transition.
How Do You Care for Rooted Butterfly Bush Cuttings?
Harden them off before potting on. The RHS says to harden off rooted softwood cuttings for about two weeks, then pot them individually. Once planted out, the RHS guide recommends a sunny spot and notes most buddlejas flower on new growth, so they can be cut hard to a low framework in early spring. See our humidity dome guide for weaning cuttings off cover.
Can You Propagate Butterfly Bush by Layering?
Yes. University of Missouri Extension lists simple layering for butterfly bush and calls it the easiest layering method for home gardeners. Bend a low branch to the ground, wound the stem about 12 inches (30 cm) from the tip, dust it with rooting stimulant, and bury it several inches deep with the shoot tip exposed. Sever and transplant it once rooted.
- Pick a flexible low branch.
- Make a 2 inch (5 cm) slanting cut at the bend.
- Dust the wound with rooting hormone.
- Bury it, leaving the tip above soil.
Can You Take Hardwood Butterfly Bush Cuttings?
Yes. University of Missouri Extension lists hardwood cuttings for butterfly bush. Iowa State University Extension says hardwood material in Iowa is best collected in late February or early March and can be stuck immediately. Choose vigorous stems from last season with thin buds, since thick-budded twigs are less likely to root.
FAQ About Butterfly Bush Cuttings
When do you take butterfly bush cuttings?
Softwood in early summer; semi-ripe July to September.
How long should butterfly bush cuttings be?
About 2 to 4 inches (5–10 cm) for softwood, per the RHS.
How long do butterfly bush cuttings take to root?
About 2 to 6 weeks.
Can butterfly bush be grown from hardwood cuttings?
Yes; Missouri Extension lists hardwood cuttings.
Is it legal to propagate butterfly bush?
Check local invasive plant rules first.
Do butterfly bush cuttings need hormone?
Optional; it speeds rooting.
Sources
- Royal Horticultural Society — How to grow buddlejas
- Royal Horticultural Society — Cuttings: softwood
- University of Maryland Extension — Butterfly Bush
- University of New Hampshire Extension — The Art of Making More
- University of Missouri Extension — Home Propagation of Garden and Landscape Plants (G6970)
- Iowa State University Extension — Propagation of Trees, Shrubs, and Vines from Hardwood Cuttings
- Photo credits (Wikimedia Commons, edited with titles): Butterfly bush (Buddleja davidii) flowers in California by Julia Sumangil (CC BY-SA 4.0); Buddleja davidii.002 – Gent by Fernando Losada Rodríguez (CC BY-SA 4.0); Butterfly world (Vanessa cardui and Buddleja davidii) by Ввласенко (CC BY-SA 3.0)