Pennsylvania Horticultural Society president, Drew Becher, talks about the growing attendance at the annual Philadelphia Flower show, and how the theme, this year “Brilliant!”, keeps the show fresh. (Adrian Higgins/The Washington Post)
Gardening columnist

In 1829, a few members of the newly formed Pennsylvania Horticultural Society gathered to show off plants that they had proudly grown and tended, some ordinary, others curiously novel like the poinsettia. Thus was held the first Philadelphia Flower Show.

Miraculously, perhaps, the show continues: It opened Saturday at the Pennsylvania Convention Center in downtown Philly and runs through Sunday. It’s safe to say that if the original participants returned they would be reaching for their smelling salts.

The show plays out in the cavernous environment of the convention center and features dozens of floral sets, hundreds of horticulturally themed vendors and thousands of competitors, who are still showing off their plants, still in search of a ribbon to affirm what they do.

Historically, big-city flower shows are like big cities themselves: They either change or decline but cannot stay the same. By all appearances, the Philadelphia show is in the midst of healthy change: Attendance climbed from 235,000 in 2010 to 270,000 last year and is on track to exceed 300,000 this year. The number of competitive entries in a feature called the horticultural court — the horticourt — is about 11,000, and the entrants’ enthusiasm has been rewarded with a new $1 million setting for the competitions that includes a fabric roof and new show benches and display backdrops.

“All the exhibitors have been just ecstatic about it,” said Diane Newbury, co-vice chairman of horticulture overseeing the judging. She was in aisles full of small but choice succulents, each in their own pots. Nearby were gigantic specimens of clivias and foxtail ferns and, farther along, slipper and moth orchids of impressive form and vigor. Beyond the orchids stood containers of daffodils, not only forced into flower but somehow twice their garden size. In the horticourt this year, “the lighting is much better,” Newbury said.

The Philadelphia Flower Show features a replica of Big Ben, part of this year’s British “Brilliant!” theme. (Matt Rourke/Associated Press)

On much of the show floor, however, the lighting still has the capacity to deaden the colors of flowers brought painstakingly into bloom out of season. The show has gotten around this, coincidentally, by moving away from the types of displays you would have found here years ago, that is, pretty little gardens given structure with arbor vitae and cypress and color with azaleas and bedding annuals, tricked into bloom in the greenhouse.

Instead, the exhibits seem to be taking plants out of the garden and using them more as design elements. This was seen in an exhibit named “Fog on the Moors” in which the creative Philadelphia floral studio of Moda Botanica used dried and blanched ferns and other primal plants to effect mist.

The exhibit reflects the strategic change that has been in force since the society appointed Sam Lemheney show designer in 2005 and Drew Becher the president in 2010.

Becher is actively moving beyond the Philadelphia region to bring in top floral and landscape designers he hopes will sharpen the show’s edge and increase its entertainment value. He has placed a lot of stock in a show attraction named the Designer’s Studio, a “Project Runway”-like high-pressure contest among floral designers.

But Becher is a big believer in staging parties, and the show also features events geared to specific groups, including an LGBT party on Sunday, a wedding night for future brides on Wednesday and on Thursday a “girls night out.”

Becher wants the show to move beyond horticulture in the same way that New York Fashion Week has become more than just runway shows, instead sparking consumer trends and becoming a cultural event unto itself.

“I want this to be the rollout of everything new for the coming season: You’ll see all the new colors, the new plants, the new garden design ideas,” he said.

Becher and his design team have tried to achieve that this year with a hip-Brit theme called “Brilliant!” that comes together with a central exhibit of Big Ben, whose massive clock face not only tells real time but morphs into amusing music videos that use Monty Python-type cut-out animations. The cast of characters include the Beatles, Mr. Bean, Joanna Lumley and even Benny Hill, still weirdly funny years after all these years. At one point when I was talking to the central feature’s designer, Chris Woods, I caught a glimpse on screen of a young Queen Elizabeth on a motorcycle.

Years ago, a British-themed exhibit would have consisted of a genteel take on the quintessential English garden, with flower borders, rose bowers and a conservatory. As Becher points out, that is no longer the garden type in Britain. The famed Chelsea Flower Show — celebrating its 100th anniversary in May — features avant-garde, high-design exhibits that draw top designers, big sponsors and prime-time TV coverage. Each main display costs well into six figures to stage.

At America’s largest flower show, Becher is also planning to move away from themes based on nations or cultures, though the British motif seemed a good one, given the buzz created by the royal wedding, the queen’s jubilee, the Olympics and that ubiquitous period soap, “Downton Abbey.”

“This isn’t about real gardening, it’s a theater, it’s a way to introduce people to the real garden that’s coming a month from now,” Woods said.

Someone trying to figure out where the Philly show has been and where it is going should meet Natasha Bieberfeld, 30, her brother Clayton Bieberfeld, 27, and his girlfriend, Gillian Brooks, 28. They showed up for society members day dressed for the part and just for the fun of it: Natasha as a character from Harry Potter, Gillian as Mary Poppins, Clayton as Bert, the chimney sweep.

The Bieberfelds’ grandparents, emigres from Germany, started a nursery and landscape business in Harleysville, Pa., in the early 1950s, and their parents used to stage exhibits at the show when they were toddlers. The Bieberfelds, who are also part of the family business, grew up with the show and like the way it is changing for their generation.

“It satisfies a deep-rooted need we have for tangibility,” Brooks said. For all the screen time of the digital generation, “they want something they can see and touch.”