http://www.bconnex.net/~mbuchana/realms/stpatric/shamrock.html#irish
THE SHAMROCK
There's a dear little plant that grows in our isle, 'Twas Saint Patrick himself, sure, that set it;
And the sun of his labor with pleasure did smile,
And with dew from his eye often wet it.
It grows through the bog, through the brake, through the mireland
And they call it the dear little Shamrock of Ireland (Irish Blessing)
THE IRISH SHAMROCK
The origins of the shamrock are lost in antiquity, but legend suggests that it was used by St. Patrick in the fifth century to demonstrate the meaning of the Trinity. The shamrock is found on Irish medieval tombs and on old copper coins, known as St. Patrick's money. The plant was reputed to have mystic powers... the leaves standing upright to warn of an approaching storm.
It is said that Patrick had a time of it trying to convince the people he met in Ireland to believe in the Holy
Trinity. Reflecting for a moment, Patrick plucked a shamrock from the earth, and pointed to the three leaves on the shamrock, living proof of the Holy Trinity. Since then, the Shamrock has become the symbol of the land of Ireland.
Only one thing is certain about the shamrock, worn by millions on St. Patrick's Day. The word is derived from the Irish 'seamrog', meaning 'summer plant', and it remains Ireland's most famous symbol.
WHAT IS A SHAMROCK
Dutch Clover, or Wood Sorrel
The Shamrock is a fragile little plant, and doesn't keep long out of its habitat. A fresh sprig in the morning will have dried and withered by noon, and can look a bit limp. Recently some bright sparks have invented a little lapel sachet in which the Shamrock is both grown and worn, and will bloom until the last of Patrick's Pot is drunk. The Irish have had a few difficulties translating ingenuity into gold over the last few thousand years, but being Green wasn't one of them.
BORD SHAMROCK
The Shamrock is not an official emblem of Ireland. That honour is reserved for The Harp. But it is used as a popular 'national' brand by all sorts of State Bodies and commercial concerns. Probably the most visible of these internationally is the Irish national airline Aer Lingus, with its heart-shaped trefoil on the tail of each plane. On St. Patrick's Day every year, Aer Lingus flies fresh shamrock to Irish Embassies all over the globe for their traditional National Day diplomatic parties. Irish uniformed personnel everywhere are also presented with Shamrock to wear for the day.
SHAMROCK HISTORY
In written English, the first reference to the Shamrock dates from 1571, and in written Irish, as seamrog, from 1707. As a badge to be worn on the lapel on the Saint's feastday, it is referred to for the first time as late as 1681.
The Shamrock was used as an emblem by the Irish Volunteers in the era of Grattan's Parliament in the 1770's, before '98 and The Act of Union. So rebellious did the wearing of the Shamrock eventually appear, that in Queen Victoria's time Irish regiments were forbidden to display it. At that time it became the custom for civilians to wear a little paper cross coloured red and green.
As a symbol of Ireland it has long been integrated into the symbology of the United Kingdom, along with the Rose, the Thistle and the Leek of England, Scotland and Wales. So today, on St. Patrick's Day, a member of the British Royal Family presents Shamrock to the Irish Guards regiment of the British Army.
THE MAGIC SHAMROCK
Three is Ireland's magic number. Hence the Shamrock.
Crone, Mother and Virgin.
Love, Valour and Wit..
Faith, Hope and Charity.
Father, Son and Holy Spirit.
Numbers played an important role in Celtic symbolism. Three was the most sacred and magical number. It multiplies to nine, which is sacred to Brigid. Three may have signified totality: past, present and future / behind, before and here / sky, earth and underworld.
Everything good in Ireland comes in threes. The rhythm of story telling in the Irish tradition is based on threefold repetition. This achieves both intensification and exaggeration. Even today in quality pub talk, a raconteur can rarely resist a third adjective, especially if it means stretching a point.
"Three accomplishments well regarded in Ireland: a clever verse, music on the harp, the art of shaving faces."