The Pennsylvania Horticultural Society turned 190 in late November. The oldest organization dedicated to botany in the United States, PHS also presented the nation's first public horticultural exhibition — the Philadelphia Flower Show.

Philly's contributions to botany predate PHS. Bartram's Garden — created by Quaker and accomplished farmer John Bartram in 1728 — is the oldest botanic garden on the continent still in existence. Along with his son William, Bartram helped cultivate hundreds of North American plants. King George III bestowed upon Bartram the title "botantist to the king" in 1765 for the farmer's role introducing attractive American foliage to England's public green spaces.

Half a century after Bartram passed away in 1777, distinguished Philadelphians gathered for the inaugural meeting of PHS. The 53 founders met on Nov. 24, 1827, to establish an institution that would advocate for "a highly instructive and interesting science for the purpose of improving the growth of vegetables, plants, trees, fruits, and flowers."

In PHS's early years, the group bounced around different intellectual centers of Philadelphia, meeting at the American Philosophical Society and the Franklin Institute, among other preeminent academic institutions. Members discussed new technologies in botany over wine tastings. They consulted with their counterparts overseas, exchanging information while amassing a library on the science.

On June 6, 1829, after just two years of operation, PHS hosted its first public flower show at the Masonic Hall on Chestnut Street. The event marked the beginning of PHS's wider cultural influence, presenting the Central American poinsettia — which has since become a staple of Christmas decor — to the U.S. public for the first time.

The Philadelphia National Gazette lauded PHS's groundbreaking show, remarking that those "who witnessed this exhibition … enjoyed the opportunity of comparing together a greater variety of plants than has at any time before been assembled among us in a single review," adding that it "would be difficult to enumerate the objects that decorated the hall with charm surpassing the effect of the most consummate art."

Throughout the following decades, PHS would continue introducing flora to the nation, as it did with the sugar beet in 1836. The organization finally moved into its own building in 1867, which allowed for ongoing horticultural displays and expanded operations. PHS would operate out of several different structures toward the end of the 19th century. Architect Frank Miles Day designed an impressive building for the organization on Broad just under Locust Street, which was completed in 1894.

Due to a dire financial situation, PHS had to relinquish its building in 1917, thereafter operating out of various office spaces during the 20th century. The organization, however, maintained a highly visible public presence.

In a collaboration with the U.S. Forestry Service and NASA, PHS helped plant the Bicentennial Moon Tree in 1975. The sycamore seed had been transported to space during the Apollo 14 mission four years earlier.

Over the years, PHS's Flower Show — the oldest indoor event of its kind in the world — has only grown in stature and influence. Each year more than 250,000 people flock to the Convention Center to enjoy awe-inspiring displays and horticultural competitions. The Flower Show has earned the Grand Pinnacle award from the International Festivals and Events Association twice, most recently in 2017. Next year's show is scheduled for March 3-11.

The organization's membership has also bloomed throughout its history, expanding from an initial membership of 80 to 27,000 today. From the Terrace Garden at Eastern State Penitentiary to the Azalea Garden at the Art Museum, PHS's work is integral to the fabric of Philadelphia, and its urban farming initiatives and mentorship programs underscore its continued impact on the city and its residents.

Patrick Glennon is a communications officer at the Historical Society of Pennsylvania.