With all of them, you can remove spent flowers and trim back straggly bits to improve appearance. In the first year you don't want to trim too much green matter as it is the food factory for the plant. Removing spent flowers promply, before the seed matures, helps the plant spent energy on growing roots instead of seeds; establishing good roots is important for continued health.

If you want the plants to seed around, let them set seed, if you don't want lots of new seedlings, don't let them set seed. The Rudbeckia tend to be bienniel, so if you want some next year, let a few seeds form. It, the Echinacea, the phlox and the beebalm are prolific self seeders and can take over your bed if you don't control them.

Buddleia will die back to the ground over winter. You can cut it down in late fall or not, depends on how "tidy" you like the winter garden.

Some of the plants are aggressive spreaders and you will need to divide them to maintain in bounds. Sign out perennial care books from your local library. When you find one that you like, with lots of useful info, buy a copy. Below, find a link to newsletters about perennials.

Here is a link that might be useful: Link to Perennial Newsletters

The Santolina: usually it's kept for the foliage not the flowers. The silvery mound against which other plants can 'show off'. Over the growing season trim it back like a hedge plant to give it shape and encourage it to produce new foliage. It will come away from the bottom and old wood but it can be a bit sensitive to frost. Be sure to snuggle up for winter.

Geranium John's Blue: it is deciduous. Once the leaves have gone red and fallen away it becomes a polite little set of red-tipped buds for waiting out the winter. Another to give frost protection to in case you get frost heave that pushes it out of the ground. New sprouts in April-May? When it warms up, anyway.

Platycodon: has yellow autumn foliage if nothing weather-drastic happens, then it dies away to a pale greyish brown lump until later in spring. Also frost-protect this growing crown with whatever is recommended for your zone.

Before they vanish for the year - DO put in labels so you can 'watch the spot' and not put a spade through when the spring planting mania strikes.

Since you are in Ohio rather than Canada, you may find the buddleia does not go completely dormant, much less die back. The common practice is to cut it back in late January or early February (in my zone 6, I prune when a long cold-spell is predicted), usually to a height of 12 to 18". It will re-sprout prolifically when the weather warms up.

Thanks for the responses to my many questions! I did go out and cut back/deadhead as suggested and things do look a lot more tidy.

Went this weekend and purchased 10 hardy mums...so many colors to choose from! Any advice on how to maintain these? :)

The rudbeckia and coneflowers I would wait to prune down until they have died back for the year. The seeds attract finches. You could also get free plants! But, it's more of a preference thing.

I would also leave the phlox be, just because of the way they grow on one central stalk, better not to risk anything.

But if you don't like the way they look, hack away. I doubt that you'll do anything bad.

Good luck with the mums, it's almost impossible to get them to overwinter here!