I've never rooted butterfly bush but I do all my other cuttings outside in the sunlight. You just have to be vigilant about keeping the soil moist.

Hi, Kevin

Last June, I took a 6 inch cutting from a butterfly bush that was growing randomly in an abandon parking lot.

I used rooting hormone and put it in a pot with regular potting soil.

I kept it on the north side of my yard where it got bright shade and no direct sunlight.

I kept the soil moist by watering every few days. That September, I planted it. It's now over 5 feet tall and has several blooms. Unfortunately, beetles were eating most of the blooms. I may still get a bloom or two.

Good luck on your cuttings,
Tina