Denise, a picture of the area you're going to plant would also help a lot. Just telling your zone really doesn't help since that only tells us how cold it gets on average in winter there. Is it humid or dry where you are? eg. Zone 5a in Nevada is very different from zone 5a in Kansas or Maine. What is your soil like? Rocky, sandy, loamy or clay? Is it acidic or alkaline - a soil test is a good idea to find out the pH because some plants only grow well in acid soil - if your azalea is happy and healthy, you probably do have acid soil.
Lots of other factors count, too. For example, what direction does the new flower bed face? Will it have sun or shade, in the morning, afternoon, all day? Are there any trees close to the bed? Big trees can have roots under the soil that will seriously make it difficult for you to grow new plants near them. How hot does it get in your average summer, and for how long?
What kind of effort are you able to put into the project - do you want low maintenance plants that will spread and take care of themselves, or flowers to cut, and things that will need winter protection?
