Raised garden beds provide a good environment for planting flowers as well as many other types of plants. You can build raised beds quickly and easily---they can have a wooden or rock frame or border, or you can simply pile up compost and other plant materials on the ground several inches tall. When you use raised beds for growing flowers, the soil is rich in plant nutrients, so you needn't fertilize your flowering plants often. The rich soil retains moisture well, making it unnecessary for you to worry about watering your flowers every day during the hot summer.
Build your raised beds by layering at least 6 to 8 inches of compost, wood chips, sawdust, peat moss, grass clippings, topsoil and other plant materials such as fallen leaves on an area about 4 feet by 8 feet. Then rake the top level with your garden rake. You can also make a circular raised bed or any other shape you desire. Build your beds in a size that enables you to reach into the center of the bed and never step on the soil material that forms the bed, which benefits your plants by keeping the soil light and not compacted.
Surround your bed with rocks, bricks or a wooden frame if you like. You can make your raised beds without a frame, but some gardeners like the appearance of a nice wooden or brick border.
Purchase flowering bedding plants that will grow to different heights and then plant the taller varieties, such as foxglove or delphinium, along the rear border of the bed. Plant shorter plants, such as pansies, violas and petunias along the front border of your bed.
Plant your flowering plants an appropriate distance apart. You might need to do a little research to determine the correct spacing for the plants you have chosen to grow. For example, plant marigolds about 6 inches apart. Larger plants that form a circular rosette, such as foxglove, need a minimum of 12 inches between plants.
Dig planting holes that are slightly larger than each plant's root system. After you remove your plants from their nursery pots, gently free the roots with your fingers, especially if the plant has become rootbound at the nursery. Then place each plant into its planting hole and fill the hole with the soil/compost mixture you dug out. Pat it down gently around the base of each plant with your palm and then water the area with a sprinkler or soaker hose, or by hand with your hose, saturating the soil well for at least 10 minutes.