Merry Christmas!
(Just to move this post down in the list)

The use of the term "disease resistant" is really tricky. For one thing, it's relative, as all roses have at least "some" susceptibility to one disease or another if given just the right (bad) conditions. I've found that minis vary in their level of disease resistance just like larger roses do, but in general tend to be similar to other modern roses. It's often helpful to pick the brains of rosarians that live in your location for information of recommended varieties, as it can vary a lot for a given rose variety depending on where it is grown. I am inclined to suggest some of the old garden rose varieties that are especially disease reistant, such as the polyantha Pinkie, or the noisette and china roses that have fairly small blooms, but your climate may be much too cold for them, I don't know. Good luck. I hope someone in your area adds to this thread.

p.s. you probably don't want to hear this, but some regular preventive anti-fungal spraying can work wonders for the health of your roses, even the one's touted as being "disease resistant."

Overall, miniatures are my most blackspot prone roses. Minnie Pearl is the most disease resistant I have. It stays clean with occasional spraying. If I neglect spraying it develops mild BS (25% or so of leaves affected) but does not totally defoliate like a lot of other minis do. Above average in disease resistance relative to other minis are Amy Grant, a light pink, and Breath of Spring, a new light yellow from Bridges. Mildew has not been much of a problem with my minis with the exception of a couple of the dark reds ones - Red Cascade & Miss Flippins. They are my fungicide indicator plants; when they start to mildew, I know it's time to spray.

Interesting. I have always considered minis pretty much bulletproof here. PM can be a problem with some of our big roses. Never seen any pm on the minis. I rarely spray here and don't bother spraying the minis when I do. I'm not an experienced mini grower. I never grew them before I met Deb. The grocery store minis she bought were so healthy and hardy we began getting 'named' minis in 2001.