Two corpse flowers are expected to bloom this week at The Huntington Library, Art Collections and Botanical Gardens in San Marino.
Stinkie grew 2.5 inches Sunday to 76.5 inches, and Green Boy 1.5 inches to 71.5 inches, according to Susan Turner-Lowe, The Huntington's vice president for communications & marketing.
Limited in-person viewing with masks required will begin Wednesday in the Conservatory, which is open 10 a.m.-5 p.m. daily and closed Tuesdays.
Reservations are not required to visit weekdays, but capacity in the Conservatory will be limited. Reservations are required for weekends and Monday holidays.
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A live stream of the corpse flowers is available here. These will be the 13th and 14th corpse flowers to bloom at The Huntington since August 1999 and second and third this month. Stankosaurus Rex bloomed July 5.
The Amorphophallus titanum, also known as a Titan Arum and corpse flower, has been called the world's largest flower, but is technically an "inflorescence," or a cluster of flowers. It can reach more than 8 feet in height when it blooms, opening to a diameter of 4 feet.
When in one of its ultra-rare blooms, it gives off an odor akin to rotting flesh, attracting insects that pollinate the flowers deep inside.
The blooming plant produces two key gases -- dimethyl disulfide and dimethyl trisulfide -- that also are present in decomposing animals and vegetables, Turner-Lowe said.
What prompts a particular plant to start the blooming process largely remains a mystery, Turner-Lowe said, but the corpse flower tends to bloom during hot weather.
When a corpse flower was first displayed at the Kew Royal Botanic Gardens in the late 19th century, at least one Victorian woman was said to have swooned when she got a whiff of the bloom.
The flower was first displayed in the United States in 1937 at the New York Botanical Garden.