No, miniature roses are rarely grafted in the US. Often, grocery store minis have four cuttings stuck by the producer in the hopes that one of them will take. It appears that the cutting for the pink rose may have not made it, but they may have accidentally included a cutting for a white mini in that pot and that's the rose you are now growing.

As for the brown leaves for a rose grown indoors, you may have had a spider mite infestation, which is common for roses grown indoors. It's good practice to wash the undersides of the leaves at least once a week to avoid an infestation. If you see those brown leaves again, wash the undersides of the leaves daily for at least three days to break the breeding cycle.

Smiles,
Lyn

Ah, I should have clarified - it was originally 4 pink minis in one pot which I separated out. This is the only one that survived, and I can attest that it used to be pink. Haven't had any blooms yet this year so who knows how it'll turn out.

This is also a window box that's outside on the balcony, and all the leaves drying up and falling off is I'm afraid my fault for not watering enough. I heard roses like well drained soil, but this is a little bit too well drained I think.

Maybe it's too much sun?

Thanks for the clarification.

Spider mites will attack roses in hot dry weather even when the rose is planted in the ground and gets plenty of moisture.

In my garden, they can defoliate a rose in a few days, so I make it a practice to always wash the undersides of the leaves at least once a week unless I see a rose getting a lot of brown leaves and then I'll wash them daily until the breeding cycle is broken.

An easy way to check for the mites is to put a white piece of paper under the leaves and tap the plant a few times. If you see a lot of small black dots, it's spider mites causing the problem. Sometimes, you can actually see webs, if you look very closely.

Smiles,
Lyn

Thanks for the tip! I take it signs of spider mites is leaves turning brown? Mine were literally just totally dried out, green, and crispy, the entire (teeny) plant! I didn't even realize they were dead at first haha. I was really afraid I'd killed my plant, but after a week or so and some fish emulsion I got a bunch of new leaves :D

Would using a spray bottle (spraying both from above and below) be good enough for washing? I can't say it's super powerful, but when I mist enough eventually droplets collect and roll off.

Would washing help for powdery mildew too? The minis in the window box (on a balcony rail, so wind pretty much on all sides) don't have any at all, while a potted clump of 3 have it really bad. I would guess that the difference in air flow is the main reason. I tried baking soda / molasses / dish soap, but then the leaves just turned yellow and died within a few days. Now the plants are looking .....dusty all over. They were doing ok, but now that it's getting warmer I'm afraid they're starting to get blackspot as well. I'll see if I can get some pics of my minis and post tomorrow.

Thanks again!

Yes, plants fully infested with spider mites will look like all of the leaves have turned brown. They truly look dead.... some are dead because you have waited too long to break the breeding cycle.

You can always buy another mister with a stronger stream. That seems to make the task easier.

As for roses which mildew. If you cannot give them enough air circulation and the plant has a propensity to mildew ... oh, well. I just pass mine along to someone who has better conditions and the warning that the plant may mildew.

There is always another rose that seems to have few problems with mildew. A few times, when I especially loved the rose, I tried moving it to another spot and that did solve the problem.

Most of the roses bred for grocery store minis, are considered to be throw-away-plants and have not been bred for disease resistance.

Smiles,
Lyn

I had a white mini rose plant that I got at the grocery store, I moved it to the ground where I also have red and pink mini roses. Later I noticed this...

Your mini isn't changing color. It has a fungal disease called Botrytis. Just remove the spotted blooms and wait for the weather to improve and it should bloom fine the next time.

Spider mites! Wow, this just solved a mystery for me. Thanks.