Lay out your circular flower bed in regard to spacing. If the bed is a circular path less than 3 feet wide, plant roses in a row to give them space. If the bed is a round shape with more space in the middle, plant several rows of roses, each with a spacing of 2 to 3 feet.
Prune away any tall foliage that shades the flower bed, as roses require six to eight hours of full sun every day. Avoid areas of the bed that receive morning shade, as this may cause mildew on rose leaves. Dig up the top 2 feet of the bed, and turn a mixture of half quick-draining soil and half organic compost into the soil. End with a combination of 1/3 natural soil, 1/3 quick-draining soil and 1/3 organic compost to give roses plenty of nutrition. Add rose-specific fertilizer before planting.
Plant rose bushes that match each other in size, growth habit and bloom color for an even, sophisticated bed. Choose red, pink, white, purple or orange cultivars of similar sizes for this look. If you want a more creative look, choose different colors, shapes and sizes. Add climbing roses to give your circular bed more dimension, but make sure you give any climbing plants a trellis or arbor for support.