Generally speaking, roses will clearly perform better in the ground. The root structure developes far more extensively, and it is easier to nurture healthy micro-organisms and fungi networks that live symbiotically with plants. The exceptions would be if sun is inadequate in the ground location, it lacks adequate drainage, or tree root competition has started to choke the rose bed. With pots you have to repot usually every three years, make sure those pots are big, and water super frequently, be very careful not to over-apply fertilizers. On the plus side, if, like me, you want to rearrange the layout of rose varieties, it is much easier.

@MikeInBatonRouge I've been using blends with neem oil and insecticidal soap, but it doesn't seem to last long. Do you know of something else (hopefully nontoxic) that works well?

@tinkercreek I am afraid I am going to eco-geek-out on you. I have gone completely chemical-free. Not only is it cheaper, but it allows the micro organisms in the soil to build a healthier growing environment for the plants. Healthy plants are more resistant to bug damage.
I used to use bayer advanced something or other, mostly for the western flower thrips that mottle flower petals. water spray blasts on undersides of leaves in hot dry weather every three days controls spider mites. I still do that, but just in hot dry seasons.

But every chemical we could use has a down side. I tried neem oil once. Many people swear by it. It is naturally derrived. It was too hot here, and the oil BADLY chemical burned the plants. Never again. Bugs vary from place to place. Japanese beetles are horrendous, largely because they are an alien invasive species without their natural preditors present in the U.S. At least they tend to have a season and then are done for a while. Thankfully they haven't made their way this far to the central Deep South.

Since I stopped using ANY sprays when I started trying to encourage butterflies. It took a while for pretator bugs to catch up, but I no longer have any serious insect problems. Those that do pop up are handled within a few weeks. I now have a chemical-free garden. ....except once in a blue moon when the misquito spray truck comes around. I can't control them. My advice is take time to wander through the roses at different times of day and even late evening to spot signs of trouble. Hand pick worms and beetles and grasshoppers you see doing damage, but leave most bugs alone. They are part of an ecosystem, and something will appreciate you leaving them to be eaten.

I just remembered, right before I snapped this photo, I found a cucumber beetle in that soft pink bloom. It had not done any damage yet, but I know they tend to, so I crushed it. I don't worry about trying to save absolutely every flower from every bit of damage. The blooms are temporary, anyway, and there will be more blooms. It is far easier and healtheir all around to, not to mention cheaper, to stop buying and using that stuff.

@tinkercreek But to answer your question after my long ramble, I guess what I use for roses is home grown compost to build healthy soil, water blasting to disrupt spider mites during dry weather, and companion plantings. Marigolds, onions and garlic and chives have bug deterrent qualities, and I read that perennial salvia helps discourage blackspot. I am not sure that is true. It certainly does not prevent it entirely. But I like the look of the interplanting anyway. I read in two different places that corn mean scattered in the soil at late winter pruning time helps to encourage a friendly soil fungus that competes with and discourages blackspot. So I plan to try that this February.

Finally but most importantly, I am always on the lookout for blackspot-resistant varieties. Ones that have performed great for me include:
Dark Desire
Belinda's Dream
Crimson Glory
Posseidon(sp?)
Madame Antoine Marie
Double Knockout
Sweet Spirit
Easy Spirit
Wedding Bells
Cramoisi Superieur
Winter Sun
Savannah
Beverly
Plum Perfect
Gaye Hammond
New Dawn
Grande Amore

That is certainly not a complete list, as there are countless I haven't grown, but there are plenty of others that were blackspot magnets. One thing I learned is even a healthy rose can occasionally come down with a bad blackspot infection but then recover and be fairly disease-free at a later time. Don't be too quick to throw it out. Observe for a couple years. The exception for me is if the plant absolutely defoliates while other roses look good.

@MikeInBatonRouge Wow, you are a gardener after my own heart! Thanks for all the great info, and I only have blackspot and spider mites to deal with, and would much prefer to avoid even the Neem/soap! I like the cornmeal idea, and can work that into the soil in a couple months. I have also read of the help from salvia, and I have wild garlic sprouting all around on its own. Marigold is what I plant around my food gardens, needing nothing else to keep bugs off there, so perhaps I should pop them in around the roses - couldn't hurt!

it is

I love the Portland Rose Garden and the Japanese garden too, thanks for reminding me of them.

I have visited the Portland Rose Garden three times. One of the very best public gardens. I miss it, living here in Louisiana. Shrevepot, LA is home to the American Rose Society rose center official gardens, so you would expect it to be spectacular. But it pales next to Portland's.

That had to be quite the stimulating hour for you in many ways

@MikeInBatonRouge I went to Buchart Gardens just north of Victoria,was absolutely blown away there

@RoyMillar oh yes, I have heard raves about Buchart, but I never made it there.

@MikeInBatonRouge I've only visited once, but it is a gardener's delight!

@MikeInBatonRouge I want to go back again

That is my fav feature, that icy pink shade.

Only a hint of one, though noses vary when it comes to rose fragrance.