The U.S. Botanic Garden Conservatory in Washington D.C. is about to get really stinky. The conservatory's titan arum - more commonly known as a corpse flower - is expected to bloom soon.

In anticipation of the flowering - the first for this titan arum, which the conservatory received in 2007 when it was the size of a lima bean - the facility will extend its hours of operation Monday until 8 p.m. Once fully open, the 250-pound flower will remain in-bloom for up to 48 hours before it quickly collapses.

Titan arum do not have an annual blooming cycle; the unpredictable plants can bloom every few years, but they have been known to take decades between flowerings.

Apart from their colossal size - the largest of the titan arum can reach 9 feet tall - the flowers are an attraction because of their putrid smell, which has been likened to rotting flesh. The stench is so strong that it's meant to lure carrion insects from miles away. Corpse flowers do not emit their rotting-flesh smell until blooming, and the stench is meant to be at its worst on the first night after flowering.

Elliot Norman, the Conservatory gardener in charge of growing the plant, told the Washington Post that the corpse flower will smell "like a very dead elephant."

While bloomings are rare, corpse flowers are increasingly not. Several botanic gardens around the United States and many more throughout the world cultivate titan arum, which is endemic to the rainforests of Indonesia's Sumatra Island. The soon-to-bloom titan arum is the fourth to be displayed at the national conservatory in the past 11 years, and the botanic garden currently has 14 accessions of the titan arum.

Last week a titan arum at the botanic garden in Brussels tantalized eyes and noses when its blooming made headlines.

The video below is a live-stream of the flower at the U.S. Botanic Garden, though at publication it appeared to be suffering from technical difficulties.

Live Video streaming by Ustream