The Hunt for a Four Leaf Clover | Desert Botanical Garden


St. Patrick’s Day is fast approaching on Wednesday, March 17. One of the most prominent traditions associated with the holiday is the wearing of the shamrock and the color green. When the Irish moved to new parts of the world and couldn’t find shamrocks, they wore green as a substitute on St. Patrick’s Day.

The word shamrock has its origins in the Irish word seamróg meaning “young clover”. While this indicates a clover is indeed a shamrock, there is more to it than that. Ireland has many small, trifoliate forbs including several clover (Trifolium) species, black medick (Medicago lupulina) and various wood sorrels (Oxalis species). Two surveys done in Ireland almost a 100 years apart asked the population to send in a sample of what they believed to be the true species of shamrock.The results included all of these species, showing that any trifoliate, clover-like leaf can be used to represent the celebratory shamrock.

Even here in the desert, you could find your own shamrock to wear on St. Patrick’s Day. Many species of Old World, clover-like, trifoliate forbs resembling the fabled shamrock have naturalized here in Arizona. Among them are 15 species including alfalfa, clovers, sweet clovers and wood sorrels. In the low desert, you’re likely to find them growing on disturbed ground and roadsides in cooler weather, although, some are limited to cooler, wetter, and high elevation areas.

There are other ways of getting your hands on a real live shamrock. Many species of Oxalis are sold commercially as houseplants via seeds, tubers, and live plants. They come in a variety of leaf colors from green to yellow to purple and flowers in shades of white, peach, pink, purple, yellow, multi-colored, and even doubled forms. One of the most common is Oxalis triangularis, sometimes labelled O. regnellii, and sold under the name shamrock plant.This is an easy-to-care-for houseplant that does best with bright light, occasional watering, and infrequent fertilization. It also benefits from a dormant period in the summer. Whether you decide to wear a shamrock or something green, hopefully the tradition brings you joy on this festive holiday.

Creeping woodsorrel (Oxalis corniculata) growing as a weed in a pot with a golden barrel cactus (Echinocactus grusonii) in the Desert Botanical Garden propagation area.

Above: Creeping woodsorrel (Oxalis corniculata) growing as a weed in a pot with a golden barrel cactus (Echinocactus grusonii) in the Desert Botanical Garden propagation area.

Here’s the complete list of naturalized (non-native) shamrocks. Learn more here. alfalfa (Medicago sativa), white sweetclover (Melilotus albus), annual yellow sweetclover (Melilotus indicus), yellow sweetclover (Melilotus officinalis), creeping woodsorrel (Oxalis corniculata) – we find this growing around DBG frequently, Bermuda sorrel (Oxalis pes-caprae), common yellow woodsorrel (Oxalis stricta), alpine clover (Trifolium dasyphyllum), pinpoint clover (Trifolium gracilentum), hollyleaf clover (Trifolium gymnocarpon), alsike clover (Trifolium hybridum), long-stalked clover (Trifolium longipes), red clover (Trifolium pretense), white clover (Trifolium repens) and cow clover (Trifolium wormskioldii).