Bringing in the May
In medieval England, people would celebrate the start of spring by going out to the country or woods—"going a-maying"—and gathering greenery and flowers, or "bringing in the may." This was described in "The Court of Love" (often attributed to Chaucer but not actually written by him) in 1561:
And furth goth all the Court, both most and lest,
To feche the floures fressh, and braunche and blome;
And namly, Hawthorn brought both page and grome.
With fressh garlandes, partie blewe and whyte,
And thaim rejoysen in their greet delyt.
Another English tradition is the maypole. Some towns had permanent maypoles that would stay up all year; others put up a new one each May. In any event, the pole would be hung with greenery and ribbons, brightly painted, and otherwise decorated, and served as a central point for the festivities.
May Day was also a time for morris dancing and other dances, often around the maypole. In the 19th century, people began to braid the maypole with ribbons by weaving in and out in the course of a dance. Other later traditions include making garlands for children and the crowning of the May Queen.
When I was a child in England, we used to make little baskets of flowers and put them on the doorstep of any special friend or mentor.
At the Catholic school, we formed a parade out to an outdoor grotto where there was a statue of Mary, and placed flowers there. It is one of my favourite memories of that school; singing "Ave Maria" as we put the fragrant blossoms in that lovely place.