What trailing plants can I plant on top of a retaining wall that will bloom all summer in Zone 7?

I want to cover a 4 foot retaining wall with colorful trailing plants that will bloom all or most of the summer. I live in the Pacific Northwest, Zone 6 - 7. Any suggestions would be greatly appreciated.

What trailing plants can I plant on top of a retaining wall that will bloom all summer in Zone 7?
A tiny pink creeping rose called 'pinkie' or bigger 'new dawn' would be great for that climate. You can also grow creeping thyme which will give you a sea of cascading crimson flowers. Clematis huvi has beautiful purple blooms. My favourite (which I'd love to grow, but can't because it's too hot here) is Wisteria Amethyst Falls. The most adorable flower, Creeping Flox, Apple blossom will take your breath away (actually, any of the flox are gorgeous). It's in the first link that I provided.
Reply:The other answer was also helpful. I failed to mention I was looking for ideas for perennials, but you gave me some good ideas for annuals that I can stick in until the perennials take over. Thank you. Report Abuse

Reply:cascading lobelia,sweet potato vine , honeysuckle, wandering Jew,purple passion,fuchsia,the list is endless. good luck