butterfly bush pruning

Question

Do you pinch off dead flowers during the summer to force new buds or just leave alone?

Answer 1

They do not need to be, but they can be if you do not like the way they look. Sometimes, removing spent blossoms can force the plant into a second bloom. Deadheading your butterfly bush will not affect its health. In fact, it's good for it. You can learn more about doing this here:
https://www.gardeningknowhow.com/ornamental/flowers/fgen/deadheading-flowers.htm

You might also want to consider pruning the bush to keep it in shape, though it isn't always necessary. Here is an article that you may find helpful: https://www.gardeningknowhow.com/ornamental/shrubs/butterfly-bush/butterfly-bush-pruning-how-to-prune-a-butterfly-bush.htm