On St John's Eve (June 23), the tradition was to light bonfires to protect the crops. Lighted branches were taken from the fire and cast into each field to ward off bad luck, or else the last embers of the fire were scattered in fields, depending on the local tradition.
In some areas, it was customary to drive cattle 'idir na tine lasta', or between two fires, on St John's Eve to ward off bad luck.
Any man who had built a new house would take a shovel of red hot sods to his new home to become the first fire in his house.
St John's fire was also used against the bad luck that people brought on themselves by building their house on a fairy path. The inhabitants of such houses were often tormented by bad luck and nocturnal disturbances.
Fairies were a major factor in the old traditions and people generally believed you should give the fairies what they wanted, be it milk, turf or whatever, to keep them on your side.
However, a freshly calved cow with plenty of milk could be protected from the fairies by applying a blessed candle to the udder, followed by a prayer and a rub of the pungent-smelling marsh marigold.
This was a combination of the six things that fairies were afraid of: something holy, something red, salt, fire, something dirty and flowing water.