From a half-block away, I noticed a lavender-tinted cloud. It was a very large wisteria growing so vigorously that the home owners had built another support to span the sidewalk. Foot-long panicles covered the structure and hung out into the street, creating a tunnel. Standing under the wisteria, looking up through the tangle of woody stems at the masses of blooms above me, I was treated to all the colors of spring: every tint and tone of the wisteria, its bright yellow leaves and the fresh greens of the trees.