I'm a UM graduate and lived in Maryland, paying taxes,  for 55 yrs. Sorry you couldn't  have given me a frederick or Washington county  climate answer.
, because I tried your web link and was not successful.

Butterfly Bush (Buddleia davidii) is an invasive species in the mid-Atlantic that we discourage gardeners from growing. They tolerate pruning well, and it's best done in late winter or early spring (March, more or less, for areas like central Maryland), not autumn. They can be cut back fairly drastically since they bloom on new growth (so no flower buds are present on branches during winter) and non-dwarf cultivars are rapid growers. Exactly how far to cut them back depends on the preferences of the gardener, but pruning to within a foot or two of the ground should be fine.

Miri

Ok. Thank  you so much. They are the only flowering anything the deer in my wooded environment  leave alone.  But the are getting  way too large.

If you have an area with enough sun (full sun ideally, like what the Butterfly Bush wants) and room for some perennials, you could try several members of the mint family that pollinators love and deer tend to leave alone, including Agastache (like Agastache foeniculum 'Blue Fortune' or similar varieties), various Mountain-mint species (Pycnanthemum), Beebalm/Bergamot (Monarda didyma and Monarda fistulosa), and herbs that are allowed to mature enough to flower (oregano, mint, marjoram, thyme). Not all of those herbs will be perennial, and they require very well-drained soil to thrive (mint is more forgiving and actually can get a bit weedy if not kept in a pot). Other perennials also loved by pollinators that deer usually avoid include White Snakeroot (Ageratina altissima), Milkweeds (Asclepias, several species), several Goldenrod species (Solidago), and Ironweed (Vernonia species).

Miri

Thank you. That's helpful.