Q&A for How to Prune Buddleia

The bloom time will be extended if you deadhead the dead flowers, so it's a good idea to remove them.

Yes, in appropriate climates a butterfly bush will come back year after year. If the conditions are not ideal, though, they may not come back.

The end of May is not a good time to prune your buddleja. Cut back 6 to 12 inches from the ground in the early spring.

Yes, you can take cuttings during the summer. Cut a 4-6 inch stem off of the plant, avoiding any flower buds. Remove the bottom 3 inches of leaves. Put the cutting into a light moist potting medium. Place the cutting in bright but indirect sunlight and keep the soil moist. Roots may take 6 weeks to develop.

Yes, May is far too late, it needs to be done in March if possible, unless there are adverse weather conditions.

Ideally, do so in the early spring (after the last frost). This is best time to prune your buddleia but I experimented last autumn and cut ours down to 2.5 ft and it came back lovely and healthy this year! However it may not be advisable to prune after September in your area, so take care.

No, this plant won’t cause problems to other plants through root spread. Keep buddleia dead headed regularly.

Cut your buddleia branches to 1-foot (30 cm) tall using pruning shears in early spring (typically March). This will promote gorgeous new growth and flowering come next summer.

Your buddleia should show signs of new growth in the early to mid-summer months, as the buddleia blooms in late summer-fall.

To stop the buddleia from spreading/growing, it's necessary to deadhead and dispose of any dead/dying blooms so that their seed pods don't propagate throughout your garden. Remove unwanted branches at the root by digging them out with a shovel to hinder your buddleia's growth.