The viridiflora tulip is in a class by itself. What distinguishes it is the green streaking that accentuates the pink petals. The color changes as the flowers mature, and the blooms last and last in the garden unlike other tulips. They have persisted in my garden for three years now, also unlike most tulips.
New this year, Lobularia 'Snow Princess' is an annual worth looking for. This photo was taken in November! What's different about this cultivar of sweet alyssum is that it is sterile, so puts all of its energy into producing blooms all summer long and into the fall. Okay, so it won't self-sow into the cracks of your walk like the standard sweet alyssum. There's no rule that you can't get some of each. Just don't put them side-by-side. 'Snow Princess' will put the the standard variety to shame.