Certified GKH Gardening Expert
The height of the Parade mini roses can vary from plant to plant; however, I believe most of them get to be 15 to 16 inches tall. You could put two in a pot and they would fill out nicely, making for a wonderful display. I am providing a link to Poulsens website as they are the hybridizers for the Parade line of miniature roses. If you know the name of your Parade roses, such as Apollo or Fiesta, you can click on the name for more information about your particular little rosebush. I do believe most of them do get bushy, so they should fill in a 10 to 12 inch pot nicely. Just remember that you do not want them to fill in too tightly, as that limits the airflow through the bush and creates a fungus breeding ground for black spot and others. https://www.gardeningknowhow.com/ornamental/flowers/roses/keeping-a-mini-rose-houseplant.htm