Back in the decades before the fall (Vat II) the May crowning of Our Blessed Mother was always done on the LAST Sunday of May. The reason being is that May 31st is the feast of the Queenship of Mary so the crowning was the closest Sunday to the feast.
Also (at least in my climate) Lilacs and peonies bloom, so as the song goes "from garden and woodland and hillside and vale", we gathered flowers in bloom and the aroma filling the church was heavenly.
I've always felt sad that the SSPX changed the tradition to the beginning of May when we can only bring store bought flowers. Also a crowning is at the end of something... probably that's why Her feast is the very end of May after a month of devotions, novenas etc.
There was a procession...first the first communicants in their white dresses and veils then Our Lady's Sodality. These were unmarried girls and young women and were considered Our Queen's ladies in waiting...all in long white gowns. All were presumed virgins as no married women were allowed in the sodality. Married women belonged to the Christian Mothers Society. The president of the sodality crowned the statue.
Often the crowning was in the church, but I remember participating when the numbers warranted an altar to be built and lavishly adorned in the attached school yard. That's when the number of parishoners far exceeded the capacity of the church.
At least one year when I participated as a senior choir member, the Bishop rented the Hamilton Tiger Cats football stadium and people from all the parishes in the diocese came for Mass and a huge procession with floats and choirs and sodalities and the various church organizations with their beautiful banners, from many parishes. Everyone brought a picnic breakfast as the fast was from midnight.
I know I have photos of the school yard event and also the stadium event. If I can scan them I'll post them.