I didn't know the clover in my lawn was so special until my son started to find several four-leaved clovers. Everyday he likes to go outside in the garden for a walk and, while admiring the flowers and the lawn, the four-leaf clovers just "jump" at him! He has already found 22 of those pretty lucky-charms in our lawn and, also, one five-leaf and one six-leaf clover, which is very rare. However, this is not so surprising coming from my son, because he has always been lucky, ever since he was born. When we bought tickets for the lottery he would always be the lucky one who had the winning ticket. Moreover, the number of his day of birth comes up frequently at the lottery. That's why I'm not that surprised when he finds the four-leaf clovers, which means that this is not merely a fairytale.
Clover, or Trifolium in Latin, is a perennial herbaceous plant in the leguminous pea family Fabaceae. The leaves are usually trifoliate, with red, purple, white or yellow spike-form flowers. Seed pods are enclosed in the calyx. The Latin name of Trifolium comes form the words "tres" and "folium" meaning three leaves, which led to the popular name of trefoil. Clover is very much cultivated as a fodder plant because of its nutritional value for the livestock. The most cultivated species are the white clover - Trifolium repens and the red clover - Trifolium pratense. Its blooms are one of the main nectar sources for the bees.  The three-leaf clover is the national symbol of Ireland, where it is called shamrock from the Irish word "seamrog" meaning "little clover". The legend about St. Patrick coming to Ireland to spread Christianity and using shamrock as a methaphor for the Christian Trinity, turned clover into a holy plant which can bring luck to everyone who wears it. An Irish bride always has a clover in her wedding bouquet, as well as the groom wears it at the boutonniere.
Having more than three leaves, the four-leaf clover means more good luck for the one who finds it. Statistics estimate the probability of finding one at 10,000 to 1. The four-leaf clover has become a universally accepted symbol of good luck, according to various old legends, some of which go back to the biblical Eve. Same for the shamrock, which was used by St. Patrick to symbolize the Holy Trinity (while the fourth leaflet, when found, may symbolize God's grace), each leaf of the four-leaf clover symbolizes something - in a less dogmatic interpretation - so that all together can bring good luck: first is for faith, second is for hope, third is for love and fourth is for luck.
The four-leaf clover is actually an uncommon variation of the three-leaf clover. The fourth leaf is often smaller than the other three. It was discovered that the fourth leaflet (or fifth, sixth, or more) is caused by a genetic mutation and special environmental conditions. Researchers from the University of Georgia discovered the gene for the four-leaf clover and they can work with it to turn simple three-leaf clover into a four-leaf clover. Of course, they are mainly produced for being commercialized as "lucky charms." Some say that it doesn't have a "luck" value when bought, but a four-leaf clover is always a nice gift. In Romania we have a beautiful tradition on March 1st - "Martisor". On that day men give their mothers, sisters, wives and daughters a "martisor" which is an amulet for luck and health. The amulets have different shapes like animals, flowers, bugs or anything symbolizing good luck - like a four-leaf clover.
The environmental conditions such as, soil pH, soil composition or pollution can influence some clover patches to produce more four-leaf clovers than others. However, pollution or chemicals couldn't have happened in the old ages - as far as we know - so how else did the mutation take place? The recent discovery of the gene responsible for the presence of more than three leaflets shows how this can happen, without the environmental's influence. The gene doesn't work well(meaning, it has a mutation) and it doesn't controll anymore the mechanism of leaf growing, so it just gets out of controll, producing more leaflets. Some scientists say that it takes only for a young leaf to be physically damaged or exposed to chemicals so it can develop four-leaf clovers. Then the mutation affects the whole family.
Whatever the reason might be, the odds of having a four-leaf clover patch in the garden are rare, so I'm feeling lucky to have it. And since all in my family are healthy, what more luck would I want?
 - http://en.wikipedia.org/wiki/Clover
 - http://www.lollysmith.com/allabsham.html#The Shamrock
 - http://www.lollysmith.com/allabsham.html#4-Leaf Clover Seed?
 - http://www.lollysmith.com/allabsham.html#4-Leaf Clover and Luck
 - http://en.wikipedia.org/wiki/Four-leaf_clover
 - http://biojournalism.com/2008/03/clover-science/
 - http://digitaljournal.com/article/292743
 - http://www.madsci.org/posts/archives/may97/862164687.Bt.r.html