The U.S. Botanic Garden’s corpse flower bloomed on Tuesday, drawing a long line of patient admirers. (U.S. Botanic Garden)

Washington’s corpse flower, or titan arum, bloomed on Tuesday in a rare morning opening of a plant the gardeners at the U.S. Botanic Garden have nicknamed Charlotte.

She took her own sweet time to unfurl the maroon cape that surrounds the central spike of the world’s largest unbranched flower. But that may be the only thing about Charlotte that is sweet. She opened at around 4 a.m. and by late morning was greeting visitors with odors that ranged from rotting cabbage to stinky trash and worse. Over the next few hours, and particularly Tuesday evening, her horticultural minders anticipate the flower to unleash the rotten flesh stink that gives it its common name.

This oddity is a native of the steamy Sumatran jungle and thus it is perfectly at home in a Washington summer — though it is a devil to keep going in other seasons and requires real horticultural skill to bring to flowering stage. In the wild, the flower’s fragrance is designed to draw pollinating beetles and flies that feed off dead animals. Instead, Charlotte is proving a magnet for humans as the botanic garden gears up to manage visitors over the next two days.

By midday a line of visitors snaked around the botanic garden conservatory to Independence Avenue.

United States Botanic Garden

The botanic garden, at 100 Maryland Ave. SW, at the foot of the Capitol, will stay open until 11 p.m. on Tuesday and Wednesday to allow visitors to experience the sight and smell of this botanical curiosity. Admission is free.

The odor is unpredictable, not as long lived as the flower itself, and is presented in waves as the blossom heats up chemically to more than 100 degrees. “There’s a bit more of the Brussels sprouts at the moment,” said spokesman Devin Dotson. “It’s a bit better than the smelly trash note it was hitting 30 minutes ago.”

When the last corpse flower bloomed here, in 2013, a total of 130,000 came to see another specimen (named George) over the course of its short life, according to the botanic garden. Once opened, the blooms last but a couple of days before the spike collapses. It takes between two and seven years for its bulb to gather enough strength to flower again.

Strangely, Charlotte’s appearance coincided with the flowering of several titan arums in the United States this week and last, at the Marie Selby Botanical Gardens in Sarasota, Fla., at the New York Botanical Garden, and at the University of Indiana in Bloomington.

One theory is that they are all talking to each other, sexually, since they can’t self pollinate.

Elliott Norman, horticulturist at the U.S. Botanic Garden, waters the corpse flower or titan arum he has raised since 2010. Since the photo was taken on July 27, the plant grew another 14 inches and finally opened on Tuesday. (Adrian Higgins/The Washington Post)

Topping out at seven foot, four inches, Charlotte has been exceptionally capricious even by titan arum standards, a species whose blooming schedule is known only to itself.

It was started by grower Elliott Norman from a pea-sized offset in 2010, and its mother plant has yet to flower, remaining in leaf between hibernations.

While Norman’s arums usually announce their blooming intention months in advance, this one only gave him a couple of weeks’ notice, and then grew far larger than its bulb size would suggest. He moved it to the conservatory’s Garden Court on July 22, but it took another week before it stopped growing, suggesting blooming was near.

Horticulturists anticipated an opening sometime between Saturday and Tuesday, but the event didn’t happen until near the very end of that window.

The blooms tend to open in the evening, and Charlotte’s dawn appearance “is to our knowledge the first to bloom in cultivation in a day-blooming cycle,” said Dotson.

This is the fifth display of a corpse flower in Washington. Prior to last week’s flowering in the Bronx, New Yorkers hadn’t seen a home grown one since 1939.

Another two titan arums are in one place, the Marie Selby Botanical Gardens in Sarasota, Fla. At the Selby Gardens, the rare double blooming took place over a span of more than a week. The first was named Seymour, the second Audrey after characters in the 1980s musical and film about a man-eating plant, “Little Shop of Horrors.”

In July 2013, the last titan arum to bloom at the U.S. Botanic Garden, nicknamed George, drew thousands of visitors. Similar crowds are enduring the heat for current bloom of Charlotte. (Matt McClain/The Washington Post)

Horticulturists at the three botanical institutions hope to share pollen for breeding purposes.

Audrey opened fully on Monday evening and by Tuesday its central spike was beginning to crumble, but that may be a sign of a successful pollination effort, said Selby Gardens spokeswoman Mischa Kirby.

These botanical gardens have many rare and marvelous plants and it’s difficult to say why the appearance of the corpse flower arouses such interest, other than folks love a freak show. These institutions love it, for the ticket sales for the ones that charge, but also because it gets people more connected to the plant kingdom.

“It’s getting people who may not be necessarily interested in plants to get an inside look at how important and interesting they are,” said Kirby.

At the USBG, Norman and plant curator Bill McLaughlin are simply thrilled to get visitors during the oppressive heat and humidity of high summer in Washington. Visitors are itching to take a selfie for their social media sites, they say. “It’s a bucket list for people to experience,” McLaughlin said.

“A large, smelly bucket,” added Norman.

The twin titans at Marie Selby Botanical Gardens, Audrey and Seymour. Audrey lasted until Tuesday after receiving pollen from Seymour, which collapsed last week. (Marie Selby Botanical Gardens)

If you’re comparing, Charlotte’s 7-foot-4, compared to Audrey’s 6-foot-2. The New York corpse flower topped out at 6 feet 4. Take that, Noo Yawk.

Charlotte “took us by surprise, and its performance has been amazing; it’s far larger than expected,” McLaughlin said.