Old iron bed frames make great 'flower'beds. They hold up to the weather better than wood ones. They can be any size you choose by make the 'bed rails' long or short. Add a wood border just inside the bed frame and fill with soil. Shortly after you plant your flowers you'll have a colorful 'quilt' of bright flowers for your bed. Flowers that spread are great for this purpose.
In the second photo just the head board has been used as a back to this flower bench. It has been attached to a dresser drawer and wood turned legs have been added to the front of the dresser. Paint everything the same color to bring it together as one unit. Just another fun way to display your flowers.
The last photo for today is a bench for people. The head board has been used for the back of the bench and the footboard has been cut in half to use for arms. Additional lumber has been used for the seat. This bench has actually used larger turned spindles for the front legs.
So next time your at a garage sale or thrift store don't pass up that old bed frame. They can be turned into something wonderful and given a brand new life.