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Name: Somee
Status: student
Grade: other
Location: Outside U.S.
Country: Nepal
Date: Fall 2013

What is the main reason to name Mirabilis jalapa as 4 'O clock plant ? Well, i searched through the net where photo periods and many terms were given which didnot clarify me so please could you answer me.


from this article:

Mirabilis Jalapa is called the 4 O'Clock plant because it doesn't open until the late afternoon.

Sincere regards, Mike Stewart


Thanks for the question. The origins of the common names of plants and animals is sometimes not clear. It is usually due to how they were discovered, or what they look like, or something about their function. Perhaps the 4'oclock plant begin opening its leaves at 4PM? In order to try to figure out why a particular common name was chosen, one would have to read about the discovery of the plant or animal. So to answer your question, I would try to look up how and when the plant was discovered. I would also consult websites on botany.

I hope this helps. Please let me know if you have more questions. Thanks Jeff

The plant has many common names:

The 4 o'clock refers to the flowers usually opening in the late afternoon.

Sincerely, Anthony R. Brach

The Four O'Clock Plant opens it flowers in the late afternoon. This may correspond to around 4 PM, but the actual time is tied to ambient temperature. The flowers then close in the morning.

Dr. Tim Durham Assistant Professor of Agronomy and Agricultural Science Ferrum College

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