Shamrocks for St. Patrick's Day: History & Growing Guide

Wearing a shamrock once risked jail or worse. Today, nursery shamrocks—symbol of St. Patrick and Ireland—signal spring and let everyone claim Irishness on March 17.

Inclusiveness extends to the plants: "shamrock" may be wood sorrel, white clover, or Medicago lupulina. All grow as houseplants post-celebration (the annual Medicago lasts into summer). Grab one and grow the green.

Legend: St. Patrick used shamrock to teach Holy Trinity. 1798 Irish Rebellion songs: wearing one meant jail/hanging by British. Now, proudly display homegrown green.

Photo by Oona Räisänen

Wood Sorrel (Oxalis)

For green-and-white shamrock houseplant, Oxalis acetosella or O. regnellii (both white flowers) are ideal. Bright indirect light, 55°F (13°C) nights to 75°F (24°C) days. Keep soil moist, not soggy; avoid sunburn. Reward: bright green leaves (close/droop at night) + periodic white flowers.

Regular dormancy: leaves die off, pot turns brown. Stop watering, move to cool dark place. When new growth emerges, resume watering, brighten spot. Repot/refresh soil (likes being potbound), divide rhizomes for more plants.

Caution: Oxalis mildly to moderately toxic to cats/dogs. Keep away from plant-chewing pets.

Photo by Jeffdelonge

Shown: Wood sorrel (Oxalis regnellii)

Bliss Garden Design: Grow outdoors in partial shade with caution—can take over, but dormancy creates bare spots. Dig up/store after first frost in cold climates.

White Clover (Trifolium repens)

True three-leafed (occasionally four) clover—probably the "real" shamrock. Commonly sold potted in March. White flowers contrast leaves.

Photo by Harry Rose

Missouri Botanical Garden: As houseplant, same light/temp as wood sorrel. Moist, not damp soil.

Natalie DeNormandie: Landscape use—mix with lawn grasses or ground cover in shade. Can become invasive outdoors.

More: Houseplant growing guides, Give Your Lawn a Taste of the Wild