Sydneysiders wait up to three hours to catch a sniff of rare corpse flower

Hundreds of people have waited in line for up to three hours to catch a sniff of the rare blooming amorphophallus titanum, or "corpse flower" at Sydney's Botanic Gardens.

The flower, known for its smell of rotting flesh, blooms for about 24 hours, and can take three or four hours to completely unfurl.

It is slowly closing over the course of today, so it's the last chance for tourists and locals alike to catch a glimpse - and sniff - of the flower.

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This particular flower, which has been dubbed by fans as "Putricia", hasn't bloomed for 15 years before this week.

Hundreds of people lined up last night to see it in full bloom, with lines reaching a three-hour wait to see the flower.

Similar crowds have gathered today and the gardens will remain open until midnight.

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The plant began blossoming at 2pm yesterday.

An audience of thousands of people have been watching a 24-hour live-stream of the flower on YouTube.

According to the Botanic Gardens, the smell is similar to that of wet socks, hot cat food, or a rotting possum.

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"If you've got some wet teenage socks, throw that into a blender, then you get some cat food you've left out in the sun, whack that in your blender, and then get some day-old vomit. Put that in the blender, blend it all up, rip the lid off," Paul Nicholson, manager of volunteer programs, said of the plant.

"That's the kind of smell you're getting.

"It's actually stunningly beautiful as well."

After the petals or "spathe" have finished blooming, they will collapse and shrivel.

A single new leaf will emerge from the underground part of the plant, and the plant will continue to grow.

It will be years before the plant flowers again.

Another corpse flower bloomed in Melbourne in January, months after another one had done the same in Geelong.

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