These plants like a well-draining soil with sand, humus and some bonemeal. The foliage is evergreen. Although these plants like cool weather, they need to come indoors during freezes. Some varieties of Hibiscus moscheutos are hardy and produce enormous blooms . But check with your nurseryman first.
Hardy hibiscus are available at many local nurseries.
Potting soils vary in nutrient levels. Many do contain a balanced supply of nutrients, but this can be used up fairly quickly by the plant, and frequent watering leaches the nutrients from the mixture. It's a good idea to replenish nutrients with regular, diluted applications of a slow-release fertilizer. These may be organic or non-organic. You could mix a little slow-release fertilizer with your potting soil, but determine what is in the bagged mix before adding anything.