We have a similar problem here in Cincinnati with a daffodil garden at the Civic Garden Center that our daffodil society maintains. Once the flowers and foliage have passed, we still need the bed to look like something. We're going to try a winter sowing of seeds of annual poppies (California and shirley types) and larkspur. This year we used some bedding annuals for summer bloom. Of course we are not retilling this bed each year as you have described, but these are just ideas to try. Bill Lee