I have had good luck re-planting those in decent potting soil and even growing them in the ground. As long as they have good drainage, don't worry about overwatering.

Check the link below for some good advice:

Here is a link that might be useful: Good Advice on rescuing supermarket mini roses

Stephanie, note that you will need to use a larger container for your rose, if it lives,
or eventually plant it in the ground.

They call them "Miniatures" because the blooms are small, but the plants can be surprisingly large.

I have seen 'Jean Kenneally' growing 6 ft tall.

Jeri

Stephanie, are you keeping your rose inside or outside? If it's inside, the answer is to move it outside to a sunny spot, if the weather permits (I don't have the foggiest notion of what zone 8 weather is like this time of year).

Roses don't grow well indoors, as mike_rivers said. These roses are intended to be more like a cut flower--they bloom and then you throw them out.

Now, that's not what we usually do with them, but that's the idea behind plants like this. They are green house grown very quckly to a small uniform size, fed heavily to make them bloom, and then sold at the supermarket or big box store as gifts. It's not that you are doing anything wrong, its that they have had absolutely perfect controlled temperature, humidity, lighting, water, fertilizer, and pesticides to make them look perfect. Now they are in the real world and they are having to deal with it for the first time in their little lives.

You can plant them in a pot outdoors (there are often 4-6 individual plants in the single container) or in the ground. They won't survive indoors. They may or may not be good in the garden--some are very good, others are terrible.