Shamrocks: How to Buy and Be Carin' for the Green

By for CAES News

Faith and begorra, 'tis almost time for the wearing o' the green. St. Patrick's Day (March 17), a traditional Irish religious day, translates to parties and parades in Georgia. But one tradition holds true on both sides of the Atlantic: shamrocks.

Why shamrocks on St. Patrick's Day? Legend has it that St. Patrick himself used the shamrock back in the fifth century to illustrate how three separate leaves united by one stem resembled the Holy Trinity.

The shamrock is found on Irish medieval tombs and old copper coins, known as St. Patrick's money. The plant was even reputed to have mystic powers because the leaves stand upright to warn of an approaching storm. Its name is derived from the Irish "seamrog," meaning "summer plant."

In some Irish-American families, a gift of a pot of "gold" (brass or gold foil will do) filled with shamrocks brings luck to the recipient.

On St. Patrick's Day, shamrocks sprout on lapels and decorate floral arrangements as well as greeting cards, balloons, hats and clothing.

"The plants sold as shamrocks in Georgia can be any of three types of plants," said Paul Thomas, a horticulturist with the University of Georgia Extension Service.

Georgians can buy a true field clover, Thomas said. Or they can get Oxalis deppei, also called the Iron Cross, which is patented as the shamrock plant. The third choice is Marsilea, or water shamrock.

"The oxalis may be the native Irish plant," Thomas said. Oxalis deppei is grown commercially. Varieties can range from bright green to purple leaves with white to rosy pink flowers.

When you shop for a pot of shamrocks, look for plants with most of the stems standing upright with unopened, fresh buds.

"If they're drooping over the side," Thomas said, "the plant has been water-stressed. It shouldn't have a lot of old flowers because it blooms a long time. Old flowers would mean it's past its blooming stage."

Shamrocks are indoor houseplants that prefer an east or west window. A southern exposure would be too hot for them, Thomas said. But shamrocks don't have to stay in the house.

"If you plant it in a protected location, a shamrock can be hardy in Georgia," he said. "Give it plenty of mulch so the ground doesn't freeze solid. It will survive.

"But it doesn't like full sun. In fact, it has to have shade. It will take Georgia's humidity and clay just fine, but not the sun," he said. "Planting it just on the surface of about four inches of forest humus would be heaven on earth to a shamrock."

Thomas said indoors or out, you should water your shamrocks regularly. But don't overfertilize them. Dilute liquid houseplant fertilizer by half and water it in about every three weeks.

The plant may lose all its leaves in the fall. But that doesn't mean it's dead.

"Shamrocks can be easily propagated from bulblets," Thomas said. "In spite of dropped leaves, if the bulb is still white, it's just quiescent, not dead. It will usually come back in the spring."