I’m sorry to say that most flowering plants only flower at one time in the year and for only a certain langht of time. My suggestion would be for you to go and ask someone at a nursery for a perennial flowering plant. A perennial just means that the plant will live for more than two years and will typically have a longer flowering period. If you plan on planting the plant outside then you may want to consider buying more than one type of plant. Like if they are for a flower garden then buy some plants that will flower in the summer months, some that will flower in the fall months, some that will flower in the winter months, and some that will flower in the spring months. That way you will always have one type of plant in bloom that will be surrounded by other plants that will add some nice greenery to the flower bed. Small evergreens shrubs and trees are always a nice pairing for flower gardens. I hope this helps. :)
Snow crocuses are the first to pop up after winter, often coming through the snow. Pansies will grow all year long if you are in the south but they can't take a harsh summer. Pansies like cool weather.
There are some beautiful plants can row in diverse weather. And I think, if you have not much time, choose cactus. Moreover, some kind of cactus plants have so really beautiful and stunning flowers. I fell in love with Gymnocalycium and Astrophytum. They are the names of a popular variety of cactus. You can see these in here: http://pinterest.com/adeniums/ or http://durhambotanicals.com. Hope you will find some plants you like soon!