desert rose flower
I have an established desert rose plant in a pot. I think it needs to transplanted into a larger pot. Not sure when to do this. The plant has never bloomed for me. I place outside in the summer months, seems to do well until late August or September when the leaves start to turn and fall off. I have managed to hold it over through the the past few winters.
Many desert roses lose their leaves in the winter, so that's no problem. My guess on why you've never seen flowers is insufficient sunlight.
Desert rose don't seem to mind being tightly potted, but if you want to repot, these tips should be helpful: https://www.gardeningknowhow.com/houseplants/hpgen/learn-more-about-repotting-houseplants.htm
I like to use a potting mix composed of 50-50 cactus soil and perlite. I think a good time for repotting would be late spring/early summer.