Matching Flowers to Vases?

(Image credit: Apartment Therapy)
Martha’s alliums defy logic: one very long stem to one very short, small glass vase

More often than we’d like to admit, we’ll go to the farmer’s market intending to buy food…and come back with more flowers than produce. By the time we get home, we’re in a frenzy to find vases for the flowers and that’s when we get flustered: we never seem to have the right vase (or glass) to hold them…not to mention we always undercut the stem, then after we realize that, we cut them too short.

By the time the ordeal is over, we’ve got too many flowers stuffed in all of our vases (and a few drinking glasses, too). Anyone have any advice on how to arrange flowers? Or any place in LA to take a workshop in flower arrangement?