Host an Event Volunteer Join Tickets

Support the plant database you love!

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
Not Yet Rated

Wednesday - April 08, 2009

From: Redding, CA
Region: California
Topic: General Botany
Title: Why do some flowers open during the day and close at night?
Answered by: Barbara Medford

QUESTION:

My son is doing a science fair project on the California Poppies. We are trying to find the definitive answer on why the flowers open during the day and close at night.

ANSWER:

Probably the reason you have not been able to find a definitive answer is that there isn't any. Although some studies have certainly been made, we couldn't find any scientific conclusions on the subject. We did, however, find the name of the function, from a website called Seeds Aside Word of the Week: Nyctinasty. Eschscholzia californica (California poppy) is just one of many plants on which this occurs. 

Since the purpose of the science fair project is no doubt to encourage students to learn how to do research and make conclusions on their own, we are going to suggest he begin by searching on the word "nyctinasty." We found the word by Googling on "flowers that close at night."  We would warn him, though, not to take everything on the Internet as absolute fact; a lot of it is opinion, not fact, a lot of it is speculation, and some of it is just wrong. He might want to list some of those speculations-like closing to hold in moisture (possible, but not proved) or the bloom was protecting its seeds from predators (maybe). 

 

More General Botany Questions

What is a Demaree Rose?
August 14, 2013 - Have been told the Apache Plume is the Wild Rose after which the Wild Rose Pass north of Ft. Davis was named. However, other research indicates it was the Demaree Rose. What is true and are there ...
view the full question and answer

Plants adding calcium to soil
June 08, 2006 - Hi, I am looking for a resource to help determine the functions of native plants. For instance, nitrogen fixing can be found in Indigo, Lead plant, lupines. Are there other plants that add back cal...
view the full question and answer

Where do plants grow?
June 23, 2007 - Where do plants grow?
view the full question and answer

More information on plants native to Taylor County TX
February 13, 2012 - Re: Thursday - September 15, 2011 QUESTION: Am looking for direction to a complete list of plants native to the Abilene, Taylor County, Texas area (trees, shrubs, grasses, cacti and other plants ...
view the full question and answer

Grafting stone fruit
April 02, 2009 - Do you know of anyone grafting the new low chill stone fruit trees to the Mexican plum to minimize cotton rot? Or would it even work?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.