Various objects were hung in a house or kept there to ensure good luck. A caul-clay from Tory island off the coast of Donegal, or house-leek (Sempervivum) would save the house from being burned and from lightening, this was grown on the roofs of thatched houses, or in specially made niches or nooks in or about the roofs or porches of houses covered with other materials. It is known by various names: ‘houseleek’ is widespread, but ‘roofleek’ occurs in parts of county Cork, ‘buachaill tí’ (houseboy) in Galway and Mayo, ‘luibh a’ tóiteáin’ in west Limerick and Kerry, ‘tóirpín’ in Clare and Tipperary, and waxplant in Offaly and Westmeath. It was also valued as a medicinal herb. Other plants grown on or about the roof of a house brought good luck and guard against fire, ‘stonecrop’ (Sedum acre) around Tramore, county Waterford and ‘snapdragon’ (Antirrhinum majus) in county Westmeath. The elder tree which grew near many houses, would protect them from lightening; the skin of a king-otter would avert general harm; there is seldom a town in Ireland where a horseshoe may not be found nailed over some house or dwelling, this was believed to bring good luck, although some believe that the shoe of an ass or donkey was much more lucky.
Take the following from a prescription in a medical manuscript of 1794:
“”Gaibh cheithre crúgh fiorasail agus dein dhá leath do gach crúgh fiorasail dein dhá leath do gach crúigh dhiobh. Cuir lethchrúgh díobh ar an ttairsicc agus leathchrúigh dhíobh ar an bhfuinneoig agus mar sin leathchrúgh ar gach doras agus fuinneoig dá mbia at an tigh agus nochan tiocfaidh sioghbhradha ná deamhan aedhir isteach tarsa.””
(Take four shoes of an entire ass, and make two halves of each shoe. Put a half-shoe on the threshold, and a half shoe on the window, and thus a half shoe over each door and window that is in the house, and there shall come no fairy or demon of the air in across them.)
St. Brigid’s crosses (placed in parts of the house and outhouses on the 31st of January, the eve of her festival; blessed palm (usually fir, yew or similar evergreen) blessed in church as part of the liturgy on Palm Sunday, holy water (blessed on Easter Saturday) brought home and sprinkled in the house, the blood of an animal or fowl slaughtered at Martinmas and likewise sprinkled in the house or a black cock (which had it’s perch over a door inside) would ward off sorcery and harm by supernatural beings; a black cat, crickets or freak eggs (placed inside the roof of the house) would ensure luck for the house and bunches of yarrow collected on the eve of St. John (June 24th) as well as May flowers (but not Whitethorn), would keep illness and mis-fortune away. People were careful never to sweep out the floor dust on a Monday, lest they sweep out their luck as well.
In the everyday life of the household there were numerous omens pertaining to the luck of the house, and these are a selection:
It was considered very lucky if a bird or a honeybee flew into the house and great care had to be taken to capture the creature and release it or otherwise ensure that it left the house unhurt. On the other hand it was believed that if a frog or a worm came into the house it was very unlucky and should be killed. Bread or meal and salt should always be in the house. The hearth should be swept clean at night, but sweepings and ashes should never be taken from the house on a Monday. Dirty water should not be thrown after dark without calling out a warning to any of the fairy or spirit world who might be near the door; this applied specially to water used for cleaning the feet.
The person who enters the house by one of two doors must go out again by the same door. Whitethorn or elder blossoms must not be brought in. Inside the house no umbrella should be opened (or you’d bring rain) and no agricultural or other implement place on the shoulder.