In Youlgrave the welldressings are displayed from Saturday to Thursday of the week usually containing 24th June, St John the Baptist day. Like Easter, no-one ever seems to be quite sure how we arrive at the date, but fittingly it falls at midsummer, the time when water was often at its scarcest (the procession often takes place in the rain however).
When the 24th of June falls on a Friday then the welldressings are worked on that day, with the blessing taking place on the 25th June (the latest it ever occurs).