Answer: The latest Burpee catalog lists several pre-designed flower gardens (shade, sun, cutting garden, etc.), and plans come along with the seeds. If you haven't seen these designs, request a copy of their catalog (http://www.burpee.com)and feast your eyes!
I know of software available for designing your own, but don't know of any websites with pre-designed gardens and accompanying plants or seeds.
Hope you find what you're looking for in the Burpee catalog!
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