That's interesting Alice. Blues tend to be soothing yet can be vivid and full of depth or light an airy. They tend not to be "friendly" with each other so for accessorizing, rather than trying to go for a match that ends in uneasy truce, it can be more fun to go for a complementary color in the orange/peach range.
Cobalt is a tricky one, such a vibrant and distinctive hue. It would be fun to lay out a cobalt blue garment and audition a lot of flowers, particular in soft orange/gold range
Teal, a color I love yet cannot "wear" can range from near aqua to almost green. I like the bluer teal with golden oranges and the greener teal with copper, rusts and deep peach.
For navy, since it is near black there are so many possibilities, white is always a safe, "crisp" and classic choice, and when one of my clients custom ordered a white grosgrain rose for her classic navy blazer over white pleated skirt, we ended up going with a white on white polkadot ribbon. [ http://flowersbyfarha.com/galleries/gallery.html 3 row, far right] and the results surprised even me! Very subtle but also very effective.
Red can also work well without, and even with a touch of white without necessarily looking like you are a walking flag.
And because navy is practically black with a wierd twist to it, you can also throw "classic" to the wind and play with a composition of various colors.
mmmm time to get out some ribbons and PLAY!