Pansies are available in a huge range of bright and cheery colors and are very easy to grow. Plant them in full/partial sun (they prefer morning sun and afternoon shade) and fertilize regularly. Keep the soil moist, like a wrung-out sponge. Pinch off spent blooms to encourage more blooms.
Pansies can be hardy to zone 4, and many gardeners see them survive all winter and push through the snow in spring. Plant pansies again in the fall and will bloom early the following spring.