-Get an early jump on spring color with cool season annuals. These plants thrive in cool weather and some even shrug off a light frost. So, as soon as garden center stock them, take some home, and plant with a nice spring container. Annuals that thrive in cool spring weather include dusty miller, dianthus, alyssum, snapdragon, petunias, and the best known pansies. They do well in that but because cool weather wont last long may not have long to enjoy them before pulling them out to make room for summer annuals. That’s why many gardeners just use them in pots. Once exception is pansy. They are so hardy. They can overwinter nearly anywhere in the US. Therefore, many gardeners plant them in flower beds in fall knowing they will return again in the following spring. When you put together spring container design, follow the thriller, spiller, filler rule. A tall focal plant like this osteospermum, some colorful fillers like this dusty miller and snapdragons; and some spillers, in this case, sweet alyssum that will cascade over the side of the pot. And don’t overlook perineals for container designs. They usually take cool weather with no problem and when warm weather hits, you can plant them in your flower bed. Here, we’re using [unk] for its colorful foliage.
SOURCE:http://www.bhg.com/gardening/flowers/annuals/annual-flowers-for-spring/